Interior train components having low smoke and low heat release, and methods of their manufacture

ABSTRACT

Seat components and claddings for railway molded or formed from a thermoplastic polymer composition comprising, based on the total weight of the composition, 50 to 93 wt. % of a specific polycarbonate; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units; 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; wherein an article having a thickness of 0.5 to 10 mm molded from the composition has a Ds-4 smoke density≦300 measured according to ISO 5659-2, and a MAHRE≦90 kW/m 2  measured according to ISO 5660-1, a multiaxial impact energy≧100 J, and a ductility in multiaxial impact of 80 to 100% at +23° C. according to ISO 6603.

BACKGROUND

This disclosure is directed to components for the interior of trains,and in particular seat components and claddings having low smoke densityand low heat release.

Standards for flame retardancy properties such as flame spread, heatrelease, and smoke generation upon burning have become increasinglystringent for articles used in mass transportation such as trains. TheEuropean Union has approved the introduction of a new harmonized firestandard for rail applications, namely EN-45545, to replace allcurrently active different standards in each member state. This standardimposes stringent requirements on heat release, smoke density, andtoxicity and flame spread properties allowed for materials used in theseapplications. Smoke density (Ds-4) in EN-45545 is the smoke densityafter four minutes measured according to ISO 5659-2, and heat release inEN-45545 is the maximum average rate of heat emission (MAHRE) measuredaccording to ISO5660-1 and flame spread in EN-45545 is the critical heatflux at extinguishment (CFE) measured according to ISO 5658-2.

“Hazard Levels” (HL1 to HL3) have been designated, reflecting the degreeof probability of personal injury as the result of a fire. The levelsare based on dwell time and are related to operation and designcategories. HL1 is the lowest hazard level and is typically applicableto vehicles that run under relatively safe conditions (easy evacuationof the vehicle). HL3 is the highest hazard level and represents mostdangerous operation/design categories (difficult and/or time-consumingevacuation of the vehicle, e.g. in underground rail cars). For eachapplication type, different test requirements for the hazard levels aredefined.

For R6 applications, covering seat components, requirements on smokedensity after four minutes measured according to ISO 5659-2 (Ds-4) areDs-4 values at or below 300 measured at 50 kW/m² for HL2 and at or below150 measured at 50 kW/m² for HL3. Requirements on the maximum averagerate of heat emission (MAHRE) measured according to ISO5660-1 are at orbelow 90 kW/m² determined at 50 kW/m² for HL2 and at or below 60 kW/m²determined at 50 kW/m² for HL3. For R6 applications, no requirements onflame spread measured according to ISO 5658-2 exist.

Typical applications falling under R1 applications include interiorvertical surfaces, such as side walls, front walls, end-walls,partitions, room dividers, flaps, boxes, hoods and louvres; interiordoors and linings for internal and external doors; window insulations,kitchen interior surfaces, interior horizontal surfaces, such as ceilingpaneling, flaps, boxes, hoods and louvres; luggage storage areas, suchas overhead and vertical luggage racks, luggage containers andcompartments; driver's desk applications, such as paneling and surfacesof driver's desk; interior surfaces of gangways, such as interior sidesof gangway membranes (bellows) and interior linings; window frames(including sealants and gaskets); (folding) tables with downward facingsurface; interior and exterior surface of air ducts, and devices forpassenger information (such as information display screens). For R1applications, requirements on smoke density after four minutes measuredaccording to ISO 5659-2 (Ds-4) are Ds-4 values at or below 300 measuredat 50 kW/m² for HL2 and at or below 150 measured at 50 kW/m for HL3.Requirements on the maximum average rate of heat emission (MAHRE)measured according to ISO5660-1 are at or below 90 kW/m² determined at50 kW/m² for HL2 and at or below 60 kW/m² determined at 50 kW/m² forHL3. Requirements on the critical heat flux at extinguishment (CFE)measured according to ISO 5658-2 are at or above 20 kW/m-for both HL2and HL3.

It is exceptionally challenging to manufacture interior articles fortrains that meet stringent smoke density standards, heat releasestandards and/or flame spread standards in addition to other materialrequirements. It is particularly challenging manufacture articles thatmeet these standards and that have good mechanical properties(especially impact/scratch resistance) and processability. Accordinglythere remains a need for interior articles for trains, and in particularseat components and claddings that have a combination of low smoke, lowheat release, and low flame spread properties. It would be a furtheradvantage if the articles could be rendered low smoke and low heatrelease without a significant detrimental effect on one or more ofmaterial cost, manufacturing ease, and mechanical properties. It wouldbe a still further advantage if the materials could be readilythermoformed or injection molded. It would still be a further advantageif such materials could be manufactured to be colorless and transparent.It would be a still further advantage if such materials were incompliance with European Railway standard EN-45545, for example, withouthaving a detrimental effect on material cost, ease of manufacture, andmechanical properties.

SUMMARY

Disclosed herein is a railway component wherein the component is a seatcomponent, and wherein the railway component is molded or formed from athermoplastic polymer composition comprising, based on the total weightof the composition, 50 to 93 wt. % of a poly(bisphenol Acarbonate)-co-(bisphenol phthalate ester); 4 to 30 wt. % of apoly(carbonate-siloxane) comprising bisphenol A carbonate units, andsiloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E hasan average value of 2 to 200, wherein the poly(carbonate-siloxane)comprises 0.5 to 55 wt. % of siloxane units based on the total weight ofthe poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphoruscompound in an amount effective to provide 0.1 to 2.0 wt. % ofphosphorus, based on the total weight of the thermoplastic polymercomposition; and optionally, up to 5 wt. % of an additive selected froma processing aid, a heat stabilizer, an ultra violet light absorber, acolorant, or a combination comprising at least one of the foregoing;wherein an article having a thickness of 0.5 to 10 mm molded from thecomposition has a Ds-4 smoke density of less than or equal to 300measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², anda MAHRE of less than or equal to 90 kW/m² measured according to ISO5660-1 on a 3 mm thick plaque at 50 kW/m², a multiaxial impact energy ator above 100 J and a ductility in multiaxial impact of 80 to 100%,measured at +23° C. at an impact speed of 4.4 m/second measuredaccording to ISO 6603 on 3.2 mm thick discs, and optionally, a meltvolume flow rate of greater than 4 cc/10 min measured at 300° C. under1.2 kg force measured according to ISO 1133.

In a specific embodiment, the composition comprises 4 to 20 wt. % of thepoly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and amolded or formed sample of the thermoplastic polymer composition has atransmission of greater than 80%0 or a haze of 5 or less measuredaccording to ASTM D1003 using the color space CIE1931 (Illuminant C anda 2° observer) at a thickness of 3 mm. These transparencies can beachieved by use of a poly(carbonate-siloxane) comprising carbonate unitsderived from bisphenol A, and repeating siloxane units, wherein thesiloxane units have an average value of 4 to 50, 4 to 15, specifically 5to 15, more specifically 6 to 15, and still more specifically 7 to 10.The transparent poly(carbonate-siloxane) can be manufactured using oneor both of the tube reactor processes described in U.S. PatentApplication No. 2004/0039145A1 or the process described in U.S. Pat. No.6,723,864 may be used to synthesize the poly(siloxane-carbonate)copolymers.

Also disclosed herein is a railway component wherein the component is aseat component, and wherein the railway component is molded or formedfrom a thermoplastic polymer composition comprising 50 to 93 wt. % of apolycarbonate copolymer comprising bisphenol A carbonate units and unitsof the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to fiveC₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; 4 to 30 wt. % of apoly(carbonate-siloxane) comprising bisphenol A carbonate units, andsiloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E hasan average value of 2 to 200, wherein the poly(carbonate-siloxane)comprises 0.5 to 55 wt. % of siloxane units based on the total weight ofthe poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphoruscompound in an amount effective to provide 0.1 to 2.0 wt. % ofphosphorus, based on the total weight of the thermoplastic polymercomposition; and optionally, up to 5 wt. % of an additive selected froma processing aid, a heat stabilizer, an ultra violet light absorber, acolorant, or a combination comprising at least one of the foregoing;wherein an article having a thickness of 0.5 to 10 mm molded from thecomposition has a Ds-4 smoke density of less than or equal to 300measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², anda MAHRE of less than or equal to 90 kW/m² measured according to ISO5660-1 on a 3 mm thick plaque at 50 kW/m², a multiaxial impact energy ator above 100 J and a ductility of 80 to 100%, measured at +23° C. at animpact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mmthick discs, and optionally, a melt volume flow rate of greater than 4cc/10 min measured at 300° C. under 1.2 kg force measured according toISO 1133.

In a specific embodiment, the composition comprises 4 to 20 wt. % of thepoly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and amolded or formed sample of the thermoplastic polymer composition has atransmission of greater than 80% or a haze of 5 or less measuredaccording to ASTM D1003 using the color space CIE1931 (Illuminant C anda 2° observer) at a thickness of 3 mm. These transparencies can beachieved by use of a PC-siloxane comprising carbonate units derived frombisphenol A, and repeating siloxane units, wherein the siloxane unitshave an average value of 4 to 50, 4 to 15, specifically 5 to 15, morespecifically 6 to 15, and still more specifically 7 to 10. Thetransparent PC-siloxanes can be manufactured using one or both of thetube reactor processes described in U.S. Patent Application No.2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 maybe used to synthesize the poly(siloxane-carbonate) copolymers.

Also described herein is a railway component wherein the component is aninterior vertical surface, such as side walls, front walls, end-walls,partitions, room dividers, flaps, boxes, hoods and louvres; an interiordoor or lining for internal and external doors; a window insulation, akitchen interior surface, an interior horizontal surface, such asceiling paneling, flaps, boxes, hoods and louvres; a luggage storagearea, such as overhead and vertical luggage racks, luggage containersand compartments; a driver's desk application, such as paneling andsurfaces of driver's desk; an interior surface of gangways, such asinterior sides of gangway membranes (bellows) and interior linings; awindow frame (including sealants and gaskets); a (folding) table withdownward facing surface; an interior or exterior surface of air ducts,or a device for passenger information, such as information displayscreens, and wherein the railway component is molded or formed from athermoplastic polymer composition comprising 50 to 93 wt. % of apoly(bisphenol A carbonate)-co-(bisphenol phthalate ester); 4 to 30 wt.% of a poly(carbonate-siloxane) comprising bisphenol A carbonate units,and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E hasan average value of 2 to 200, wherein the poly(carbonate-siloxane)comprises 0.5 to 55 wt. % of siloxane units based on the total weight ofthe poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphoruscompound in an amount effective to provide 0.1 to 2.0 wt. % ofphosphorus, based on the total weight of the thermoplastic polymercomposition; and optionally, up to 5 wt. % of an additive selected froma processing aid, a heat stabilizer, an ultra violet light absorber, acolorant, or a combination comprising at least one of the foregoing;wherein an article having a thickness of 0.5 to 10 mm molded from thecomposition has a Ds-4 smoke density of less than or equal to 300measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², anda MAHRE of less than or equal to 90 kW/m² measured according to ISO5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux atextinguishment (CFE) of equal to or more than 20 kW/m² measuredaccording to ISO 5658-2 at a 3 mm thick plaque, a multiaxial impactenergy at or above 100 J and a ductility of 80 to 100%, measured at +23°C. at an impact speed of 4.4 m/second measured according to ISO 6603 on3.2 mm thick discs, and optionally, a melt volume flow rate of greaterthan 4 cc/10 min measured at 300° C. under 1.2 kg force measuredaccording to ISO 1133.

In a specific embodiment, the composition comprises 4 to 20 wt. % of thepoly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and amolded or formed sample of the thermoplastic polymer composition has atransmission of greater than 80% or a haze of 5 or less measuredaccording to ASTM D1003 using the color space CIE1931 (Illuminant C anda 2° observer) at a thickness of 3 mm. These transparencies can beachieved by use of a PC-siloxane comprising carbonate units derived frombisphenol A, and repeating siloxane units, wherein the siloxane unitshave an average value of 4 to 50, 4 to 15, specifically 5 to 15, morespecifically 6 to 15, and still more specifically 7 to 10. Thetransparent PC-siloxanes can be manufactured using one or both of thetube reactor processes described in U.S. Patent Application No.2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 maybe used to synthesize the poly(siloxane-carbonate) copolymers.

Also described herein is a railway component wherein the component is aninterior vertical surface, such as side walls, front walls, end-walls,partitions, room dividers, flaps, boxes, hoods and louvres; an interiordoor or lining for internal and external doors; a window insulation, akitchen interior surface, an interior horizontal surface, such asceiling paneling, flaps, boxes, hoods and louvres; a luggage storagearea, such as overhead and vertical luggage racks, luggage containersand compartments; a driver's desk application, such as paneling andsurfaces of driver's desk; an interior surface of gangways, such asinterior sides of gangway membranes (bellows) and interior linings; awindow frame (including sealants and gaskets); a (folding) table withdownward facing surface; an interior or exterior surface of air ducts,or a device for passenger information, such as information displayscreens, and wherein the railway component is molded or formed from athermoplastic polymer composition comprising, based on the total weightof the composition, 50-93 wt. % of a polycarbonate copolymer comprisingbisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to fiveC₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; 4 to 30 wt. % of apoly(carbonate-siloxane) comprising bisphenol A carbonate units, andsiloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E hasan average value of 2 to 200, wherein the poly(carbonate-siloxane)comprises 0.5 to 55 wt. % of siloxane units based on the total weight ofthe poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphoruscompound in an amount effective to provide 0.1 to 2.0 wt. % ofphosphorus, based on the total weight of the thermoplastic polymercomposition; and optionally, up to 5 wt. % of an additive selected froma processing aid, a heat stabilizer, an ultra violet light absorber, acolorant, or a combination comprising at least one of the foregoing;wherein an article having a thickness of 0.5 to 10 mm molded from thecomposition has a Ds-4 smoke density of less than or equal to 300measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², anda MAHRE of less than or equal to 90 kW/m² measured according to ISO5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux atextinguishment (CFE) of equal to or more than 20 kW/m² measuredaccording to ISO 5658-2 at a 3 mm thick plaque, a multiaxial impactenergy at or above 100 J and a ductility of 80 to 100%, measured at +23°C. at an impact speed of 4.4 m/second measured according to ISO 6603 on3.2 mm thick discs, and optionally, a melt volume flow rate of greaterthan 4 cc/10 min measured at 300° C. under 1.2 kg force measuredaccording to ISO 1133.

In a specific embodiment, the composition comprises 4 to 20 wt. % of thepoly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and amolded or formed sample of the thermoplastic polymer composition has atransmission of greater than 80% or a haze of 5 or less measuredaccording to ASTM D1003 using the color space CIE1931 (Illuminant C anda 2° observer) at a thickness of 3 mm. These transparencies can beachieved by use of a PC-siloxane comprising carbonate units derived frombisphenol A, and repeating siloxane units, wherein the siloxane unitshave an average value of 4 to 50, 4 to 15, specifically 5 to 15, morespecifically 6 to 15, and still more specifically 7 to 10. Thetransparent PC-siloxanes can be manufactured using one or both of thetube reactor processes described in U.S. Patent Application No.2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 maybe used to synthesize the poly(siloxane-carbonate) copolymers.

Further described as a railway component that is a molded or extrudedtrain seat component or cladding comprising a thermoplastic compositioncomprising, based on the total weight of the composition: 50 to 93 wt. %of combination comprising (i) 5 to 50 wt. % of bisphenol A polycarbonateand (ii) 50 to 95 wt. % of a poly(bisphenol arylate) of the formula

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂alkenyl. C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are eachindependently 0 to 4, and X^(a) is a bridging group between the twoarylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—. —C(O)—,a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) andR^(d) are each independently hydrogen or C₁₋₁₀ alkyl, or a group of theformula —C(═R^(e))— wherein Re is a divalent C₁₋₁₀ hydrocarbon group,based on the weight of the combination; and siloxane units of theformula

or a combination comprising at least one of the foregoing, wherein E hasan average value of 2 to 200, wherein the poly(carbonate-siloxane)comprises 0.5 to 55 wt. % of siloxane units based on the total weight ofthe poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphoruscompound in an amount effective to provide 0.1 to 2.0 wt. % ofphosphorus, based on the total weight of the thermoplastic polymercomposition; and optionally, up to 5 wt. % of an additive selected froma processing aid, a heat stabilizer, an ultra violet light absorber, acolorant, or a combination comprising at least one of the foregoing;wherein the component has: a smoke density after 4 minutes (Ds-4) ofequal to or less than 300 measured according to ISO 5659-2 on a 3 mmthick plaque at 50 kW/m², an integral of the smoke density as a functionof time up to 4 minutes (VOF4) of equal to or less than 600 measuredaccording to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximumaverage heat release (MAHRE) of equal to or less than 90 kW/m² measuredaccording to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and aductility in multiaxial impact of 80 to 100%, measured at +23° C. at animpact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mmthick discs.

In a specific embodiment, the composition comprises 4 to 20 wt. % of thepoly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and amolded or formed sample of the thermoplastic polymer composition has atransmission of greater than 80% or a haze of 5 or less measuredaccording to ASTM D1003 using the color space CIE1931 (Illuminant C anda 2° observer) at a thickness of 3 mm. These transparencies can beachieved by use of a PC-siloxane comprising carbonate units derived frombisphenol A, and repeating siloxane units, wherein the siloxane unitshave an average value of 4 to 50, 4 to 15, specifically 5 to 15, morespecifically 6 to 15, and still more specifically 7 to 10. Thetransparent PC-siloxanes can be manufactured using one or both of thetube reactor processes described in U.S. Patent Application No.2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 maybe used to synthesize the poly(siloxane-carbonate) copolymers.

In yet another embodiment, a method of manufacture of the railwaycomponent comprises molding or extruding the above-describedcompositions to form the component.

The above described and other features are exemplified by the followingFigures, Detailed Description, and Examples.

BRIEF DESCRIPTION OF THE DRAWINGS

A description of the figures, which are meant to be exemplary and notlimiting, is provided in which:

FIG. 1 shows the effect of the SiPC2 content in PPP-BP/BPA on smokedensity (Ds-4);

FIG. 2 shows the effect of the silicon content in PPP-BP/BPA on smokedensity (Ds-4);

FIG. 3 shows the effect of the content of SiPC2 in PC-Ester1 on smokedensity (Ds-4):

FIG. 4 shows the effect of the silicon content from variouspolycarbonate-siloxane copolymers in PC-Ester1 on smoke density (Ds-4);and

FIG. 5 shows the effect of the silicon content from variouspolysiloxanes in PC-Ester1 on smoke density (Ds-4).

DETAILED DESCRIPTION

The inventors hereof have developed articles for use in train interiors,including seat components and claddings. The articles have low smokedensity characteristics, in particular Ds-4 measured according toISO5659-2, and low heat release characteristics, in particular improvedMAHRE measured according to ISO5660-1, and can unexpectedly be obtainedby use of specific thermoplastic polycarbonate compositions. Thus, ithas been discovered that the addition of the small amount ofpoly(carbonate-siloxane) copolymer, a polydialkylsiloxane, or acombination comprising at least one of the foregoing to poly(bisphenol Acarbonate)-co-(bisphenol phthalate esters) or polycarbonate copolymercomprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to fiveC₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; results in a significant decrease inthe smoke density (Ds-4) of the polycarbonate polymers measuredaccording to ISO 5659-2.

The results are particularly surprising because neither polycarbonatepolymers alone nor poly(carbonate-siloxane) copolymers alone have a goodperformance in the ISO5659 smoke density test. For example, mostpolycarbonate polymers have DS-4 values far exceeding 480 measuredaccording to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², andpoly(carbonate-siloxane) copolymers and polydialkylsiloxanes can haveDS-4 values greater than 1,000 measured according to ISO 5659-2 on a 3mm thick plaque at 50 kW/m². However, the combination of thepolycarbonate polymer and the poly(carbonate-siloxane) copolymer,polydialkylsiloxane, or a combination comprising at least one of theforegoing, and an organophosphorus compound in an amount effective toprovide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of thethermoplastic polymer composition, results in a composition having DS-4values below 300 measured according to ISO 5659-2 on a 3 mm thick plaqueat 50 kW/m². The compositions also have low heat release with MAHREvalues below 90 kW/m² measured according to ISO 5660-1 on a 3 mm thickplaque at 50 kW/m².

Furthermore, the results are surprising because it is discovered thatonly polysiloxanes with alkyl siloxane groups, for example,polydimethylsiloxane, are capable of reducing smoke density of apolycarbonate polymer, whereas polysiloxanes containing phenyl siloxaneunits (only phenyl siloxane or combined with alkyl siloxane) are evendetrimental for smoke density. This is highly unexpected, as for otherflame properties, such as UL V-0 compliance, the siloxane of choice istypically phenyl based siloxane such as octaphenylcyclotetrasiloxane orpolyphenylmethylsiloxane rather than polydialkylsiloxanes such aspolydimethylsiloxane.

With this discovery, it is now possible to manufacture seat componentsand claddings having the required low smoke densities (Ds-4) measuredaccording to ISO5659-2 on 3 mm thick samples at 50 kW/m² and low heatrelease (MAHRE) measured according to ISO 5660-1 on 3 mm thick samplesat 50 kW/m² and optionally low flame spread measured according to ISO5658-2.

The polycarbonate compositions can further have excellent impactstrength. The polycarbonate compositions can also be formulated to havelow melt viscosities, which renders them suitable for injection molding.Such compositions are especially useful in the manufacture of seatcomponents and claddings. The compositions can further have very hightransmission and low haze which makes it possible to manufacturetransparent or diffusive seat components and claddings. In particular,the seat components and claddings molded or extruded from polycarbonatecompositions containing a first polycarbonate selected frompoly(bisphenol A carbonate)-co-(bisphenol phthalate esters) orpolycarbonate copolymer comprising bisphenol A carbonate units and unitsof the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to fiveC₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; and a second polymer different fromthe first polycarbonate, the second polymer comprising apoly(carbonate-siloxane) copolymer, a polydialkylsiloxane, or acombination comprising at least one of the foregoing, and anorganophosphorus compound in an amount effective to provide 0.1 to 2.0wt. % of phosphorus, based on the total weight of the thermoplasticpolymer composition; wherein an article molded from the firstpolycarbonate has a smoke density after 4 minutes (DS-4) of greater than600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m²;an article molded from the second polymer has a smoke density after 4minutes (DS-4) of greater than 600 measured according to ISO 5659-2 on a3 mm thick plaque at 50 kW/m²; and an article molded from thecomposition has a smoke density after 4 minutes (DS-4) of smaller than300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m²,low heat release with MAHRE values below 90 kW/m² measured according toISO 5660-1 on a 3 mm thick plaque at 50 kW/m² and optionally low flamespread with CFE values above 20 kW/m² measured according to ISO 5658-2.

In a particularly advantageous feature, the thermoplastic compositionscan have very low smoke density with Ds-4 values at or below 300measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², alow maximum average heat release (MAHRE) at or below 90 kJ/m² measuredaccording to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², whileallowing sufficient melt flow for injection molding of relatively largeparts, while simultaneously retaining sufficient practical impactresistance characteristics. Optionally, the compositions can have acritical heat flux at extinguishment (CFE) at or above 20 kW/m² measuredaccording to ISO 5658-2 on a 3 mm thick plaque. Furthermore, thesecompositions can have a transmission of 80% or more or a haze of 5 orless, each measured using the color space CIE1931 (Illuminant C and a 2°observer) at a thickness of 3.2 mm measured according to ASTM D1003.

As used herein, the term “polycarbonate” and “polycarbonate polymer”refers to compounds having first repeating first units that arebisphenol carbonate units of formula (1)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are eachindependently 0 to 4, and X^(a) is a bridging group between the twoarylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—,a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) andR^(d) are each independently hydrogen or C₁₋₁₁ alkyl, or a group of theformula —C(═R^(e))— wherein Re is a divalent C₁₋₁₀ hydrocarbon group.Exemplary X^(a) groups include methylene, ethylidene, neopentylidene,and isopropylidene. The bridging group X^(a) and the carbonate oxygenatoms of each C₆ arylene group can be disposed ortho, meta, or para(specifically para) to each other on the C₆ arylene group.

In a specific embodiment, R^(a) and R^(b) are each independently a C₁₋₁₀alkyl group, p and q are each independently 0 to 1, and X^(a) is asingle bond, —O—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₉ alkylidene of formula—C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independentlyhydrogen or C₁₋₈ alkyl, or a group of the formula —C(═R^(e))— wherein Reis a divalent C₁₋₉ hydrocarbon group. In another specific embodiment,R^(a) and R^(b) are each independently a methyl group, p and q are eachindependently 0 to 1, and X^(a) is a single bond, a C₁₋₇ alkylidene offormula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independentlyhydrogen or C₁₋₆ alkyl. In an embodiment, p and q is each 1, and R^(a)and R^(b) are each a C₁₋₃ alkyl group, specifically methyl, disposedmeta to the oxygen on each ring. The bisphenol carbonate units (1) canbe derived from bisphenol A, where p and q are both 0 and X^(a) isisopropylidene.

The polycarbonate units in the copolymers can be produced from dihydroxycompounds of the formula (2)

HO—R¹—OH  (2)

wherein R¹ is a bridging moiety. Thus, the bisphenol carbonate units (1)are generally produced from the corresponding bisphenol compounds offormula (3)

wherein R^(a) and R^(b), p and q, and X^(a) are the same as in formula(1).

Some illustrative examples of specific bisphenol compounds that can beused to produce units (1) include 4,4′-dihydroxybiphenyl,bis(4-hydroxyphenyl)methane, 1,2-bis(4-hydroxyphenyl)ethane,2-(4-hydroxyphenyl)-2-(3-hydroxyphenyl)propane,1,2,2-bis(3-methyl-4-hydroxyphenyl)propane,2,2-bis(3-ethyl-4-hydroxyphenyl)propane,2,2-bis(3-n-propyl-4-hydroxyphenyl)propane,2,2-bis(3-isopropyl-4-hydroxyphenyl)propane,2,2-bis(3-sec-butyl-4-hydroxyphenyl)propane,2,2-bis(3-t-butyl-4-hydroxyphenyl)propane,2,2-bis(3-cyclohexyl-4-hydroxyphenyl)propane,2,2-bis(3-allyl-4-hydroxyphenyl)propane,2,2-bis(3-methoxy-4-hydroxyphenyl)propane, bis(4-hydroxyphenyl)ether,bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfoxide,bis(4-hydroxyphenyl)sulfone, or a combination comprising at least one ofthe foregoing bisphenolic compounds.

Specific examples of bisphenol compounds that can be used in theproduction of bisphenol carbonate units (1) include1,1-bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane,2,2-bis(4-hydroxyphenyl)propane (“bisphenol A” or “BPA”),2,2-bis(4-hydroxyphenyl) butane, 2,2-bis(4-hydroxyphenyl) octane.1,1-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl) n-butane,2,2-bis(4-hydroxy-2-methylphenyl)propane,1,1-bis(4-hydroxy-t-butylphenyl)propane, and combinations comprising atleast one of the foregoing bisphenol compounds.

The polycarbonate polymer can be a copolymer that further comprisessecond repeating units. The second repeating units can be bisphenolcarbonate units (provided that they are different from the bisphenolcarbonate units (1)), or arylate ester units. In particular, the secondunits can be bisphenol carbonate units of formula (4)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkenyl, C₃₋₈cycloalkyl, or C₁₋₁₂ alkoxy, p and q are each independently integers of0 to 4, and X^(b) is C₂₋₃₂ bridging hydrocarbon group that is not thesame as the X^(a) in the polycarbonate copolymer. The bridging groupX^(b) and the carbonate oxygen atoms of each C₆ arylene group can bedisposed ortho, meta, or para (specifically para) to each other on theC₆ arylene group.

In an embodiment, X^(b) is a substituted or unsubstituted C₃₋₁₈cycloalkylidene, a substituted or unsubstituted C₃₋₁₈ cycloalkylene, asubstituted or unsubstituted C₁₂₋₂₅ alkylidene of formula—C(R^(c))(R^(d))— wherein R^(c) and R^(d) are each independentlyhydrogen, C₁₋₂₄ alkyl, C₄₋₁₂ cycloalkyl, C₆₋₁₂ aryl, C₇₋₁₂ arylalkylene,C₁₋₁₂ heteroalkyl, or cyclic C₇₋₁₂ heteroarylalkyl, or a group of theformula —C(═R^(c))— wherein Re is a divalent C₁₂₋₃₁ hydrocarbon group.Exemplary X^(b) groups include cyclohexylmethylidene, 1,1-ethene,2-[2.2.1]-bicycloheptylidene, cyclohexylidene, cyclopentylidene,cyclododecylidene, and adamantylidene.

In an embodiment. X^(b) is a substituted or unsubstituted C₅₋₃₂alkylidene of formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are eachindependently hydrogen, C₄₋₁₂ cycloalkyl, C₆₋₁₂ aryl, C₇₋₁₂arylalkylene, C₁₋₁₂ heteroalkyl, a substituted or unsubstituted group ofthe formula —C(═R^(c))— wherein Re is a divalent C₁₂₋₃₁ hydrocarbyl, asubstituted or unsubstituted C₅₋₁₈ cycloalkylidene, a substituted orunsubstituted C₅₋₁₈ cycloalkylene, a substituted or unsubstituted C₃₋₁₈heterocycloalkvlidene, or a group of the formula -B¹-G-B²- wherein B¹and B² are the same or different C₁₋₆ alkylene group and G is a C₃₋₁₂cycloalkylidene group or a C₆₋₁₆ arylene group.

For example, X^(b) can be a substituted C₃₋₁₈ heterocycloalkylidene offormula (4a)

wherein R^(r), R^(P), R^(q), and R^(t) are each independently hydrogen,oxygen, or C₁₋₁₂ organic groups; I is a direct bond, a carbon, or adivalent oxygen, sulfur, or —N(Z)— where Z is hydrogen, halogen,hydroxy, C₁₋₁₂ alkyl, C₁₋₁₂ alkoxy, or C₁₋₁₂ acyl; h is 0 to 2, j is 1or 2, i is an integer of 0 or 1, and k is an integer of 0 to 3, with theproviso that at least two of R^(r), R^(p), R^(q), and R^(t) takentogether are a fused cycloaliphatic, aromatic, or heteroaromatic ring.It will be understood that where the fused ring is aromatic, the ring asshown in formula (3) will have an unsaturated carbon-carbon linkagewhere the ring is fused. When k is one and i is 0, the ring as shown informula (6) contains 4 carbon atoms, when k is 2, the ring contains 5carbon atoms, and when k is 3, and the ring contains 6 carbon atoms. Inan embodiment, two adjacent groups (e.g., R^(q) and R^(t) takentogether) form an aromatic group, and in another embodiment. R^(q) andR^(t) taken together form one aromatic group and R^(r) and R^(p) takentogether form a second aromatic group. When R^(q) and R^(t) takentogether form an aromatic group, R^(P) can be a double-bonded oxygenatom, i.e., a ketone.

Specific second bisphenol carbonate repeating units of this type arephthalimidine carbonate units of formula (4b)

wherein R^(a), R^(b), p, and q are as in formula (4), R³ is eachindependently a C₁₋₆ alkyl, j is 0 to 4, and R⁴ is hydrogen, C₁₋₆ alkyl,phenyl optionally substituted with 1 to 5 C₁₋₆ alkyl groups. In anembodiment, R^(a) and R^(b) are each independently C₁₋₃ alkyl. Forexample, the phthalimidine carbonate units are of formula (4c)

wherein R⁵ is hydrogen, phenyl optionally substituted with up to fiveC₁₋₆ alkyl groups, or C₁₋₄ alkyl. In an embodiment, R⁵ is hydrogen,phenyl, or methyl. Carbonate units (4c) wherein R⁵ is phenyl can bederived from 2-phenyl-3,3′-bis(4-hydroxy phenyl)phthalimidine (alsoknown as N-phenyl phenolphthalein bisphenol, or “PPP-BP”) (also known as3,3-bis(4-hydroxyphenyl)-2-phenylisoindolin-1-one).

Other bisphenol carbonate repeating units of this type are the isatincarbonate units of formula (4d) and (4e)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, p and q areeach independently 0 to 4, and R^(i) is C₁₋₁₂ alkyl, phenyl optionallysubstituted with 1 to 4 C₁₋₁₀ alkyl groups, or benzyl optionallysubstituted with 1 to 5 C₁₋₁₀ alkyl groups. In an embodiment, R^(a) andR^(b) are each methyl, p and q are each independently 0 or 1, and R¹ isC₁₋₄ alkyl or phenyl.

Examples of bisphenol carbonate units (4) wherein X^(b) is a substitutedor unsubstituted C₃₋₈ cycloalkylidene include thecyclohexylidene-bridged, alkyl-substituted bisphenol of formula (4f)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, R^(g) isC₁₋₁₂ alkyl, p and q are each independently 0 to 4, and t is 0 to 10. Ina specific embodiment, at least one of each of R^(a) and R^(b) aredisposed meta to the cyclohexylidene bridging group. In an embodiment,R^(a) and R^(b) are each independently C₁₋₄ alkyl, R^(g) is C₁₋₄ alkyl,p and q are each 0 or 1, and t is 0 to 5.

In another specific embodiment, R^(a), R^(b), and R^(g) are each methyl,r and s are each 0 or 1, and t is 0 or 3, specifically 0.

Examples of other bisphenol carbonate units (4) is a substituted orunsubstituted C₃₋₁₈ cycloalkylidene include adamantyl units of formula(4g) and fluorenyl units of formula (4h)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, and p and qare each independently 1 to 4. In a specific embodiment, at least one ofeach of R^(a) and R^(b) are disposed meta to the cycloalkylidenebridging group. In an embodiment, R^(a) and R^(b) are each independentlyC₁₋₃ alkyl, and p and q are each 0 or 1; specifically, R^(a), R^(b) areeach methyl, p and q are each 0 or 1, and when p and q are 1, the methylgroup is disposed meta to the cycloalkylidene bridging group. Carbonatescontaining units (4a) to (4g) are useful for making polycarbonates withhigh glass transition temperatures (T^(g)) and high heat distortiontemperatures.

Bisphenol carbonate units (4) are generally produced from thecorresponding bisphenol compounds of formula (5)

wherein R^(a), R^(b), p, q, and X^(b) are the same as in formula (4).

Specific examples of bisphenol compounds of formula (5) includebis(4-hydroxyphenyl)diphenylmethane,1,1-bis(4-hydroxy-t-butylphenyl)propane. 1,6-dihydroxynaphthalene,2,6-dihydroxynaphthalene,6,6′-dihydroxy-3,3,3′,3′-tetramethylspiro(bis)indane (“spirobiindanebisphenol”), 2,6-dihydroxydibenzo-p-dioxin, 2,6-dihydroxythianthrene,2,7-dihydroxyphenoxathiin, 2,7-dihydroxy-9,10-dimethvlphenazine,3,6-dihydroxydibenzofuran, 3,6-dihydroxydibenzothiophene,2,7-dihydroxycarbazole, and 2,6-dihydroxythianthrene3,3-bis(4-hydroxyphenyl)phthalimidine,2-phenyl-3,3-bis(4-hydroxyphenyl)phthalimidine (PPP-BP), and1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane (DMBPC). Combinationscomprising at least one of the foregoing dihydroxy compounds can also beused.

The relative mole ratio of first bisphenol carbonate units (1) andsecond bisphenol carbonate units (4) can vary from 99:1 to 1:99,depending on the desired characteristics of the polycarbonatecomposition, including glass transition temperature (“Tg”), impactstrength, ductility, flow, and like considerations. For example, themole ratio of units (1):units (4) can be from 90:10 to 10:90, from 80:20to 20:80, from 70:30 to 30:70, or from 60:40 to 40:60. When bisphenolcarbonate units (1) units are derived from bisphenol A, the bisphenol Aunits are generally present in an amount from 50 to 99 mole %, based onthe total moles of units in the polycarbonate copolymer. For example,when bisphenol carbonate units (1) are derived from bisphenol A, andbisphenol units (4) are derived from PPP-BP, the mole ration of units(1) to units (4) can be from 99:1 to 50:50, or from 90:10 to 55:45.

Other carbonate units can be present in any of the polycarbonatecopolymers described herein in relatively small amounts, for exampleless than 20 mole %, less than 10 mole %, or less than 5 mole %, basedon the total moles of units in the polycarbonate copolymer. The othercarbonate units can be derived from aliphatic or aromatic dihydroxycompounds having 1 to 32 carbon atoms, for example1,6-dihydroxnaphthalene, 2,6-dihydroxynaphthalene,6,6′-dihydroxy-3,3,3′,3′-tetramethylspiro(bis)indane (“spirobiindanebisphenol”), 2,6-dihydroxydibenzo-p-dioxin, 2,6-dihydroxythianthrene,2,7-dihydroxyphenoxathin, 2,7-dihydroxy-9,10-dimethylphenazine,3,6-dihydroxydibenzofuran, 3,6-dihydroxydibenzothiophene,2,7-dihvdroxycarbazole, and 2,6-dihydroxythianthrene. A specificaromatic dihydroxy compound includes the monoaryl dihydroxy compounds offormula (6)

wherein each R^(h) is independently a halogen atom, a C₁₋₁₀ hydrocarbylsuch as a C₁₋₁₀ alkyl group, a halogen-substituted C₁₋₁₀ alkyl group, aC₆₋₁₀ aryl group, or a halogen-substituted C₆₋₁₀ aryl group, and n is 0to 4. The halogen is usually bromine. In an embodiment, no halogens arepresent. Specific monoaryl dihydroxy compounds (6) include resorcinol,substituted resorcinol compounds such as 5-methyl resorcinol, 5-ethylresorcinol, 5-propyl resorcinol, 5-butyl resorcinol, 5-t-butylresorcinol, 5-phenyl resorcinol, 5-cumyl resorcinol, 2,4,5,6-tetrafluororesorcinol, 2,4,5,6-tetrabromo resorcinol, and the like; catechol;hydroquinone; and substituted hydroquinones such as 2-methylhydroquinone, 2-ethyl hydroquinone, 2-propyl hydroquinone. 2-butylhydroquinone. 2-t-butyl hydroquinone, 2-phenyl hydroquinone, 2-cumylhydroquinone, 2,3,5,6-tetramethyl hydroquinone, 2,3,5,6-tetra-t-butylhydroquinone, 2,3,5,6-tetrafluoro hydroquinone, 2,3,5,6-tetrabromohydroquinone. A combination comprising at least one of the foregoingaromatic dihydroxy compounds can be used. In an embodiment, thepolycarbonate copolymer comprises carbonate units of formulas (1) and(4), and less than 10 mole % of units derived from monoaryl dihydroxycompounds (6), i.e., monoaryl carbonate units of the formula (6a)

wherein each R^(h) is independently a halogen or C₁₋₁₀ hydrocarbongroup, and n is 0 to 4. Specifically, each R^(h) is independently a C₁₋₃alkyl group, and n is 0 to 1, or n is 0. In another embodiment, nocarbonate units other than units of formulas (1) and (4) are present inthe polycarbonate copolymer.

Polycarbonates can be manufactured by processes such as interfacialpolymerization and melt polymerization. Although the reaction conditionsfor interfacial polymerization can vary, an exemplary process generallyinvolves dissolving or dispersing a dihydric phenol reactant in aqueouscaustic soda or potash, adding the resulting mixture to awater-immiscible solvent medium, and contacting the reactants with acarbonate precursor in the presence of a catalyst such as, for example,a tertiary amine or a phase transfer catalyst, under controlled pHconditions, e.g., 8 to 10. The water immiscible solvent can be, forexample, methylene chloride, 1,2-dichloroethane, chlorobenzene, toluene,and the like.

Exemplary carbonate precursors include a carbonyl halide such ascarbonyl bromide or carbonyl chloride, or a haloformate such as abishaloformates of a dihydric phenol (e.g., the bischloroformates ofbisphenol A, hydroquinone, or the like) or a glycol (e.g., thebishaloformate of ethylene glycol, neopentyl glycol polyethylene glycol,or the like). Combinations comprising at least one of the foregoingtypes of carbonate precursors can also be used. In an embodiment, aninterfacial polymerization reaction to form carbonate linkages usesphosgene as a carbonate precursor, and is referred to as a phosgenationreaction.

Among tertiary amines that can be used are aliphatic tertiary aminessuch as triethylamine and tributylamine, cycloaliphatic tertiary aminessuch as N,N-diethyl-cyclohexylamine, and aromatic tertiary amines suchas N,N-dimethylaniline. Among the phase transfer catalysts that can beused are catalysts of the formula (R³)₄Q⁺X⁻, wherein each R₃ is the sameor different, and is a C₁₋₁₀ alkyl group; Q is a nitrogen or phosphorusatom; and X is a halogen atom or a C₁₋₈ alkoxy group or C₆₋₁₈ aryloxygroup. Exemplary phase transfer catalysts include (CH₃(CH₂)₃)₄N⁺X⁻,(CH₃(CH₂)₃)₄P⁺X⁻, (CH₃(CH₂)₅)₄N⁺X⁻, (CH₃(CH₂)₆)₄N⁺X⁻, (CH₃(CH₂)₄)₄N⁺X⁻,CH₃(CH₃(CH₂)₃)₃N⁺X⁻, and CH₃(CH₃(CH₂)₂)₃N⁺X⁻, wherein X is Cl⁻, Br⁻, aC₁₋₈ alkoxy group or a C₆₋₁₈ aryloxy group. An effective amount of aphase transfer catalyst can be 0.1 to 10 wt. %, or 0.5 to 2 wt. %, eachbased on the weight of bisphenol in the phosgenation mixture.

Alternatively, melt processes can be used to make the polycarbonates.Melt polymerization may be conducted as a batch process or as acontinuous process. In either case, the melt polymerization conditionsused may comprise two or more distinct reaction stages, for example, afirst reaction stage in which the starting dihydroxy aromatic compoundand diaryl carbonate are converted into an oligomeric polycarbonate anda second reaction stage wherein the oligomeric polycarbonate formed inthe first reaction stage is converted to high molecular weightpolycarbonate. Such “staged” polymerization reaction conditions areespecially suitable for use in continuous polymerization systems whereinthe starting monomers are oligomerized in a first reaction vessel andthe oligomeric polycarbonate formed therein is continuously transferredto one or more downstream reactors in which the oligomeric polycarbonateis converted to high molecular weight polycarbonate. Typically, in theoligomerization stage the oligomeric polycarbonate produced has a numberaverage molecular weight of about 1,000 to about 7,500 Daltons. In oneor more subsequent polymerization stages the number average molecularweight (Mn) of the polycarbonate is increased to between about 8,000 andabout 25,000 Daltons (using polycarbonate standard).

The term “melt polymerization conditions” is understood to mean thoseconditions necessary to effect reaction between a dihydroxy aromaticcompound and a diaryl carbonate in the presence of a transesterificationcatalyst. Typically, solvents are not used in the process, and thereactants dihydroxy aromatic compound and the diaryl carbonate are in amolten state. The reaction temperature can be about 100° C. to about350° C., specifically about 180° C. to about 310° C. The pressure may beat atmospheric pressure, supra-atmospheric pressure, or a range ofpressures from atmospheric pressure to about 15 torr in the initialstages of the reaction, and at a reduced pressure at later stages, forexample about 0.2 to about 15 torr. The reaction time is generally about0.1 hours to about 10 hours.

The diaryl carbonate ester can be diphenyl carbonate, or an activateddiphenyl carbonate having electron-withdrawing substituents on the arylgroups, such as bis(4-nitrophenyl)carbonate,bis(2-chlorophenyl)carbonate, bis(4-chlorophenyl)carbonate, bis(methylsalicyl)carbonate, bis(4-methylcarboxylphenyl)carbonate,bis(2-acetylphenyl) carboxylate, bis(4-acetylphenyl) carboxylate, or acombination comprising at least one of the foregoing.

Catalysts used in the melt polymerization of polycarbonates can includealpha or beta catalysts. Beta catalysts are typically volatile anddegrade at elevated temperatures. Beta catalysts are therefore preferredfor use at early low-temperature polymerization stages. Alpha catalystsare typically more thermally stable and less volatile than betacatalysts.

The alpha catalyst can comprise a source of alkali or alkaline earthions. The sources of these ions include alkali metal hydroxides such aslithium hydroxide, sodium hydroxide, and potassium hydroxide, as well asalkaline earth hydroxides such as magnesium hydroxide and calciumhydroxide. Other possible sources of alkali and alkaline earth metalions include the corresponding salts of carboxylic acids (such as sodiumacetate) and derivatives of ethylene diamine tetraacetic acid (EDTA)(such as EDTA tetrasodium salt, and EDTA magnesium disodium salt). Otheralpha transesterification catalysts include alkali or alkaline earthmetal salts of a non-volatile inorganic acid such as NaH₂PO₃, NaH₂PO₄,Na₂HPO₃, KH₂PO₄, CsH₂PO₄, Cs₂HPO₄, and the like, or mixed salts ofphosphoric acid, such as NaKHPO₄, CsNaHPO₄, CsKHPO₄, and the like.Combinations comprising at least one of any of the foregoing catalystscan be used.

Possible beta catalysts can comprise a quaternary ammonium compound, aquaternary phosphonium compound, or a combination comprising at leastone of the foregoing. The quaternary ammonium compound can be a compoundof the structure (R⁴)₄N⁺X⁻, wherein each R⁴ is the same or different,and is a C₁₋₂₀ alkyl group, a C₄₋₂₀ cycloalkyl group, or a C₄₋₂₀ arylgroup; and X⁻ is an organic or inorganic anion, for example a hydroxide,halide, carboxylate, sulfonate, sulfate, formate, carbonate, orbicarbonate. Examples of organic quaternary ammonium compounds includetetramethyl ammonium hydroxide, tetrabutyl ammonium hydroxide,tetramethyl ammonium acetate, tetramethyl ammonium formate, tetrabutylammonium acetate, and combinations comprising at least one of theforegoing. Tetramethyl ammonium hydroxide is often used. The quaternaryphosphonium compound can be a compound of the structure (R⁵)₄P⁺X⁻,wherein each R⁵ is the same or different, and is a C₁₋₂₀ alkyl group, aC₄₋₂₀ cycloalkyl group, or a C₄₋₂₀ aryl group; and X⁻is an organic orinorganic anion, for example a hydroxide, halide, carboxylate,sulfonate, sulfate, formate, carbonate, or bicarbonate. Where X⁻ is apolyvalent anion such as carbonate or sulfate it is understood that thepositive and negative charges in the quaternary ammonium and phosphoniumstructures are properly balanced. For example, where R²⁰-R²³; are eachmethyl groups and X⁻ is carbonate, it is understood that X⁻ represents2(CO₃ ⁻²). Examples of organic quaternary phosphonium compounds includetetramethyl phosphonium hydroxide, tetramethyl phosphonium acetate,tetramethyl phosphonium formate, tetrabutyl phosphonium hydroxide,tetrabutyl phosphonium acetate (TBPA), tetraphenyl phosphonium acetate,tetraphenyl phosphonium phenoxide, and combinations comprising at leastone of the foregoing. TBPA is often used.

The amount of alpha and beta catalyst used can be based upon the totalnumber of moles of dihydroxy compound used in the polymerizationreaction. When referring to the ratio of beta catalyst, for example aphosphonium salt, to all dihydroxy compounds used in the polymerizationreaction, it is convenient to refer to moles of phosphonium salt permole of the dihydroxy compound, meaning the number of moles ofphosphonium salt divided by the sum of the moles of each individualdihydroxy compound present in the reaction mixture. The alpha catalystcan be used in an amount sufficient to provide 1×10⁻² to 1×10⁻⁸ moles,specifically, 1×10⁻⁴ to 1×10⁻⁷ moles of metal per mole of the dihydroxycompounds used. The amount of beta catalyst (e.g., organic ammonium orphosphonium salts) can be 1×10⁻² to 1×10⁻⁵, specifically 1×10⁻³ to 1×10⁴moles per total mole of the dihydroxy compounds in the reaction mixture.

Branched polycarbonate blocks can be prepared by adding a branchingagent during polymerization. These branching agents includepolyfunctional organic compounds containing at least three functionalgroups selected from hydroxyl, carboxyl, carboxylic anhydride,haloformyl, and mixtures of the foregoing functional groups. Specificexamples include trimellitic acid, trimellitic anhydride, trimellitictrichloride, tris-p-hydroxy phenyl ethane, isatin-bis-phenol,tris-phenol TC (1,3,5-tris((p-hydroxyphenyl)isopropyl)benzene),tris-phenol PA (4(4(1,1-bis(p-hydroxyphenyl)-ethyl) alpha,alpha-dimethyl benzyl)phenol), 4-chloroformyl phthalic anhydride,trimesic acid, and benzophenone tetracarboxylic acid. The branchingagents can be added at a level of about 0.05 to about 5 wt. %.Combinations comprising linear polycarbonates and branchedpolycarbonates can be used.

All types of polycarbonate end groups are contemplated as being usefulin the polycarbonate composition, provided that such end groups do notsignificantly adversely affect desired properties of the compositions. Achain stopper (also referred to as a capping agent) can be includedduring polymerization. The chain stopper limits molecular weight growthrate, and so controls molecular weight in the polycarbonate. Exemplarychain stoppers include certain mono-phenolic compounds, mono-carboxylicacid chlorides, and/or mono-chloroformates. Mono-phenolic chain stoppersare exemplified by monocyclic phenols such as phenol and C₁-C₂₂alkyl-substituted phenols such as p-cumyl-phenol, resorcinolmonobenzoate, and p- and tertiary-butyl phenol; and monoethers ofdiphenols, such as p-methoxyphenol. Alkyl-substituted phenols withbranched chain alkyl substituents having 8 to 9 carbon atom can bespecifically mentioned. Certain mono-phenolic UV absorbers can also beused as a capping agent, for example4-substituted-2-hydroxybenzophenones and their derivatives, arylsalicylates, monoesters of diphenols such as resorcinol monobenzoate,2-(2-hydroxyaryl)-benzotriazoles and their derivatives.2-(2-hydroxyaryl)-1,3,5-triazines and their derivatives, and the like.Mono-carboxylic acid chlorides can also be used as chain stoppers. Theseinclude monocyclic, mono-carboxylic acid chlorides such as benzoylchloride, C₁-C22 alkyl-substituted benzoyl chloride, toluoyl chloride,halogen-substituted benzoyl chloride, bromobenzoyl chloride, cinnamoylchloride, 4-nadimidobenzoyl chloride, and combinations thereof;polycyclic, mono-carboxylic acid chlorides such as trimellitic anhydridechloride, and naphthoyl chloride; and combinations of monocyclic andpolycyclic mono-carboxylic acid chlorides. Chlorides of aliphaticmonocarboxylic acids with less than or equal to about 22 carbon atomsare useful. Functionalized chlorides of aliphatic monocarboxylic acids,such as acryloyl chloride and methacryoyl chloride, are also useful.Also useful are mono-chloroformates including monocyclic,mono-chloroformates, such as phenyl chloroformate, alkyl-substitutedphenyl chloroformate, p-cumyl phenyl chloroformate, toluenechloroformate, and combinations thereof.

In an embodiment, the polycarbonate is a branched polycarbonatecomprising units as described above; greater than or equal to 3 mole %,based on the total moles of the polycarbonate, of moieties derived froma branching agent; and end-capping groups derived from an end-cappingagent having a pKa between about 8.3 and about I. The branching agentcan comprise trimellitic trichloride, 1,1,1-tris(4-hydroxyphenyl)ethaneor a combination of trimellitic trichloride and1,1,1-tris(4-hydroxyphenyl)ethane, and the end-capping agent is phenolor a phenol containing a substituent of cyano group, aliphatic groups,olefinic groups, aromatic groups, halogens, ester groups, ether groups,or a combination comprising at least one of the foregoing. In a specificembodiment, the end-capping agent is phenol, p-t-butylphenol,p-methoxyphenol, p-cyanophenol, p-cumylphenol, or a combinationcomprising at least one of the foregoing.

The polycarbonate copolymers comprising carbonate units (1) andcarbonate units (4) can have an intrinsic viscosity, as determined inchloroform at 25° C., of about 0.3 to about 1.5 deciliters per gram(dl/gm), specifically about 0.45 to about 1.0 dl/gm. The polycarbonatecopolymers can have a weight average molecular weight of about 10,000 toabout 200,000 gmol, specifically about 20,000 to about 100,000 g/mol, asmeasured by gel permeation chromatography (GPC), using a crosslinkedstyrene-divinylbenzene column and calibrated to polycarbonatereferences. GPC samples are prepared at a concentration of about 1 mgper ml, and are eluted at a flow rate of about 1.5 ml per minute.

In another embodiment the polycarbonate polymer is a polycarbonatecopolymer, in particular a poly(carbonate-arylate ester) containing thefirst repeating bisphenol carbonate units (1) and repeating arylateester units of formula (7)

wherein Ar¹ is a C₆₋₃₂ hydrocarbyl group containing at least onearomatic group, e.g., a phenyl, naphthalene, anthracene, or the like. Inan embodiment. Ar¹ is derived from an aromatic bisphenol as describedabove in connection with units (1) and (4), a monoaryl dihydroxycompound (6), or a combination comprising different bisphenol ormonoaryl dihydroxy compounds. Thus, arylate ester units (7) can bederived by reaction of isophthalic acid, terephthalic acid, or acombination comprising at least one of the foregoing (referred to hereinas a “phthalic acid”), with any of the aromatic bisphenols describedabove, a monoaryl dihydroxy compound (6), or a combination comprising atleast one of the foregoing. The molar ratio of isophthalate toterephthalate can be 1:99 to 99:1, or 80:20 to 20:80, or 60:40 to 40:60.

The poly(carbonate-arylate ester) comprising first bisphenol carbonateunits (1) and arylate ester units (7) can be alternating or blockcopolymers of formula (8)

wherein R¹ and Ar¹ are as defined in formulae (1) and (7), respectively.

In general, the copolymers are block copolymers containing carbonateblocks and ester blocks. The weight ratio of total ester units to totalcarbonate units in the copolymers can vary broadly, for example from99:1 to 1:99, or from 95:5 to 5:95, specifically from 90:10 to 10:90, ormore specifically from 90:10 to 50:50, depending on the desiredproperties of the polycarbonate composition. The molar ratio ofisophthalate to terephthalate in the ester units of the copolymers canalso vary broadly, for example from 0:100 to 100:0, or from 92:8 to8:92, more specifically from 98:2 to 45:55, depending on the desiredproperties of the polycarbonate composition. For example, the weightratio of total ester units to total carbonate can be 99:1 to 40:60, or90:10 to 50:40, wherein the molar ratio of isophthalate to terephthalateis from 99:1 to 40:50, more specifically 98:2 to 45:55, depending on thedesired properties of the polycarbonate composition.

Additional carbonate units derived from the dihydroxy compound used toform the arylate ester units (7) can also be present as described above,for example in amounts of less than 20 mole %, less than 10 mole %, orless than 5 mole %, based on the total moles of units in thepolycarbonate copolymer. It is also possible to have additional arylateester units present derived from reaction of the phthalic acid with thedihydroxy compound used to form the carbonate units, for example inamounts of less than 20 mole %, less than 10 mole %, less than 5 mole %,or less than 1 mole % based on the total moles of units in thecopolymer. In an embodiment, the combination of such additionalcarbonate units and such additional arylate ester units are present inan amount of less than 20 mole %, less than 10 mole %, less than 5 mole%, or less than 1 mole % based on the total moles of units in thecopolymer.

A specific poly(carbonate-arylate ester) is apoly(carbonate)-co-(bisphenol arylate ester) comprising carbonate units(1), specifically bisphenol carbonate units, even more specificallybisphenol A carbonate units and repeating bisphenol arylate ester units.Bisphenol arylate units comprise residues of phthalic acid and abisphenol, for example a bisphenol (2). In an embodiment the bisphenolarylate ester units are of formula (7a)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are eachindependently 0 to 4, and X^(a) is a bridging group between the twoarylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—,a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) andR^(d) are each independently hydrogen or C₁₋₁₁ alkyl, or a group of theformula —C(═R^(c))— wherein R^(e) is a divalent C₁₋₁₀ hydrocarbon group.In an embodiment, p and q is each 0 or 1, and R^(a) and R^(b) are each aC₁₋₃ alkyl group, specifically methyl, disposed meta to the oxygen oneach ring, and X^(a) is an alkylidene of the formula —C(R^(c))(R^(d))—wherein R^(c) and R^(d) are each C₁₋₆ alkyl. The bisphenol can bebisphenol A, where p and q are both 0 and X^(a) is isopropylidene.

In a specific embodiment, the polycarbonate copolymer is apoly(bisphenol A carbonate)-co-(bisphenol A-phthalate-ester) of formula(8a)

wherein y and x represent the weight percent of arylate-bisphenol Aester units and bisphenol A carbonate units, respectively. Generally,the units are present as blocks. In an embodiment, the weight percent ofester units y to carbonate units x in the copolymers is 50:50 to 99:1,or 55:45 to 90:10, or 75:25 to 95:5. Copolymers of formula (8a)comprising 35 to 45 wt. % of carbonate units and 55 to 65 wt. % of esterunits, wherein the ester units have a molar ratio of isophthalate toterephthalate of 45:55 to 55:45 are often referred to aspoly(carbonate-ester)s (PCE), and copolymers comprising 15 to 25 wt. %of carbonate units and 75 to 85 wt. % of ester units having a molarratio of isophthalate to terephthalate from 98:2 to 88:12 are oftenreferred to as poly(phthalate-carbonate)s (PPC).

In another embodiment, a specific polycarbonate copolymer is apoly(carbonate)-co-(monoaryl arylate ester) containing carbonate units(1) and repeating monoaryl arylate ester units of formula (7b)

wherein each R^(h) is independently a halogen atom, a C₁₋₁₀ hydrocarbylsuch as a C₁₋₁₀ alkyl group, a halogen-substituted C₁₋₁₀ alkyl group, aC₆₋₁₀ aryl group, or a halogen-substituted C₆₋₁₀ aryl group, and n is 0to 4. Specifically, each R^(h) is independently a C₁₋₄ alkyl, and n is 0to 3, 0 to 1, or 0. These poly(carbonate)-co-(monoaryl arylate ester)copolymers are of formula (8b)

wherein R¹ is as defined in formula (1) and R^(h), and n are as definedin formula (7b), and the mole ratio of x:m is 99:1 to 1:99, specifically80:20 to 20:80, or 60:40 to 40:60.

Specifically, the monoaryl-arylate ester unit (7b) is derived from thereaction of a combination of isophthalic and terephthalic diacids (orderivatives thereof) with resorcinol (or reactive derivatives thereof)to provide isophthalate-terephthalate-resorcinol (“ITR” ester units) offormula (7c)

wherein m is 4 to 100, 4 to 90, 5 to 70, more specifically 5 to 50, orstill more specifically 10 to 30. In an embodiment, the ITR ester unitsare present in the polycarbonate copolymer in an amount greater than orequal to 95 mol %, specifically greater than or equal to 99 mol %, andstill more specifically greater than or equal to 99.5 mol % based on thetotal moles of ester units in the copolymer. Such(isophthalate-terephthalate-resorcinol)-carbonate copolymers (“ITR-PC”)can possess many desired features, including toughness, transparency,and weatherability. ITR-PC copolymers can also have desirable thermalflow properties. In addition, ITR-PC copolymers can be readilymanufactured on a commercial scale using interfacial polymerizationtechniques, which allow synthetic flexibility and compositionspecificity in the synthesis of the ITR-PC copolymers.

A specific example of a poly(carbonate)-co-(monoaryl arylate ester) is apoly(bisphenol A carbonate)-co-(isophthalate-terephthalate-resorcinolester) of formula (8c)

wherein m is 4 to 100, 4 to 90, 5 to 70, more specifically 5 to 50, orstill more specifically 10 to 30, and the mole ratio of x:n is 99:1 to1:99, specifically 90:10 to 10:90. The ITR ester units are present inthe poly(carbonate-arylate ester) copolymer in an amount greater than orequal to 95 mol %, specifically greater than or equal to 99 mol %, andstill more specifically greater than or equal to 99.5 mol % based on thetotal moles of ester units. Other carbonate units, other ester units, ora combination comprising at least one of the foregoing can be present,in a total amount of 1 to 20 mole % based on the total moles of units inthe copolymers, for example resorcinol carbonate units of formula (20)and bisphenol ester units of formula (7a):

wherein, in the foregoing formulae, R^(h) is each independently a C₁₋₁₀hydrocarbon group, n is 0 to 4, R^(a) and R^(b) are each independently aC₁₋₁₂ alkyl, p and q are each independently integers of 0 to 4, andX^(a) is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, or a C₁₋₁₃alkylidene of formula —C(R^(c))(R^(d))— wherein R^(c) and R^(d) are eachindependently hydrogen or C₁₋₁₂ alkyl, or a group of the formula—C(═R^(c))— wherein Re is a divalent C₁₋₁₂ hydrocarbon group. Thebisphenol ester units can be bisphenol A phthalate ester units of theformula

In an embodiment, poly(bisphenol Acarbonate)-co-(isophthalate-terephthalate-resorcinol ester) (8c)comprises 1 to 20 mol % of bisphenol A carbonate units. 20-98 mol % ofisophthalic acid-terephthalic acid-resorcinol ester units, andoptionally 1 to 60 mol % of resorcinol carbonate units, isophthalicacid-terephthalic acid-bisphenol A phthalate ester units, or acombination comprising at least one of the foregoing.

The polycarbonate copolymers comprising arylate ester units aregenerally prepared from polyester blocks. The polyester blocks can alsobe prepared by interfacial polymerization. Rather than utilizing thedicarboxylic acid or diol per se, the reactive derivatives of the acidor diol, such as the corresponding acid halides, in particular the aciddichlorides and the acid dibromides can be used. Thus, for exampleinstead of using isophthalic acid, terephthalic acid, or a combinationcomprising at least one of the foregoing acids, isophthaloyl dichloride,terephthaloyl dichloride, or a combination comprising at least one ofthe foregoing dichlorides can be used. The polyesters can also beobtained by melt-process condensation as described above, by solutionphase condensation, or by transesterification polymerization wherein,for example, a dialkyl ester such as dimethyl terephthalate can betransesterified with the dihydroxy reactant using acid catalysis, togenerate the polyester blocks. Branched polyester blocks, in which abranching agent, for example, a glycol having three or more hydroxylgroups or a trifunctional or multifunctional carboxylic acid has beenincorporated, can be used. Furthermore, it can be desirable to havevarious concentrations of acid and hydroxyl end groups on the polyesterblocks, depending on the ultimate end use of the composition.

The polycarbonate copolymers comprising arylate ester units can have anM_(w) of 2,000 to 100,000 g/mol, specifically 3,000 to 75,000 g/mol,more specifically 4,000 to 50,000 g/mol, more specifically 5,000 to35.000 g/mol, and still more specifically 17,000 to 30.000 g/mol.Molecular weight determinations are performed using GPC using a crosslinked styrene-divinyl benzene column, at a sample concentration of 1milligram per milliliter, and as calibrated with polycarbonatestandards. Samples are eluted at a flow rate of about 1.0 ml/min withmethylene chloride as the eluent.

In still another embodiment, the composition for manufacture of thetrain components can comprise a combination of a bisphenol Apolycarbonate and a poly(bisphenol arylate ester) instead of, or inaddition to, the above-described polycarbonate copolymers. The bisphenolA polycarbonate can be branched, or manufactured to contain end groupsas described above, and can have an M_(w) of 2,000 to 100,000 g/mol,specifically 3,000 to 75,000 g/mol. Molecular weight determinations areperformed using GPC using a cross linked styrene-divinyl benzene column,at a sample concentration of 1 milligram per milliliter, and ascalibrated with polycarbonate standards. Samples are eluted at a flowrate of about 1.0 ml/min with methylene chloride as the eluent.

The poly(bisphenol arylate) is of formula (21)

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl. C₁₋₁₂alkenyl, C₁₋₁₂ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are eachindependently 0 to 4, and X^(a) is a bridging group between the twoarylene groups, and is a single bond, —O—, —S—, —S(O)—. —S(O)₂—, —C(O)—,a C₁₋₁₂ alkylidene of the formula —C(R^(c))(R^(d))— wherein R^(c) andR^(d) are each independently hydrogen or C₁₋₁₀ alkyl, or a group of theformula —C(═R^(c))— wherein R^(c) is a divalent C₁₋₁₀ hydrocarbon group.In an embodiment, p and q z are each 0, and X^(a) is a bridging groupbetween the two arylene groups, and is a single bond, —O—, —S—, —S(O)—,—S(O)₂—, —C(O)—, a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))—wherein R^(c) and R^(d) are each independently hydrogen or C₁₋₁₀ alkyl.Specifically, p and q are each 0 and X^(a) is isopropylidene, to providea poly(bisphenol A-arylate).

The relative ratios of the bisphenol A polycarbonate and thepoly(bisphenol arylate) can be varied to provide the desired properties,for example from (i) 5 to 50 wt. %, or 35 to 45 wt. % of a bisphenol Apolycarbonate and (ii) 50 to 95 wt. %, specifically 55 to 65 wt. % of apoly(bisphenol A arylate), specifically a poly(bisphenol A arylate),based on the weight of the combination.

The polydialkylsiloxanes are silicone oils of low volatility, forexample silicone oils with a viscosity of from 10 millipascal-second(mPa-s, also known as centipoise, cps) to 100,000,000 mPa-s at 25° C.are preferable, and silicone oils with a viscosity of from 20 mPa-s to10,000,000 mPa-s at 25° C. Examples of such silicone oils include oilshaving linear, partially branched linear, cyclic, or branched molecularstructures, with oils having linear or cyclic structures beingspecifically mentioned. The silicone oils have no, or substantially noreactive groups, for example no alkenyl groups, no silicon-bondedhydrogen atoms, no silanol groups, and no silicon-bonded hydrolyzablegroups. The alkyl groups can be the same or different and can have 1 to10 carbon atoms, 1 to 6 carbon atoms, or 1 to 3 carbon atoms. In anembodiment, the silicone oil is a polydimethylsiloxane, for example apolydimethylsiloxane having a viscosity from 50 to 1,000 mPa-s at 25° C.

The poly(carbonate-siloxane) copolymers, also referred to as“PC-siloxane,” can contain bisphenol carbonate units (1) and repeatingsiloxane units (also known as “diorganosiloxane units”). The siloxaneunits can be polysiloxane units of formula (9)

wherein each R is independently a C₁₋₁₃ monovalent hydrocarbyl group.For example, each R can independently be a C₁₋₁₃ alkyl group. C₁₋₁₃alkoxy group, C₂₋₁₃ alkenyl group, C₂₋₁₃ alkenyloxy group, C₃₋₆cycloalkyl group, C₃₋₆ cycloalkoxy group, C₆₋₁₄ aryl group, C₆₋₁₀aryloxy group, C₇₋₁₃ arylalkyl group, C₇₋₁₃ arylalkoxy group, C₇₋₁₃alkylaryl group, or C₇₋₁₃ alkylaryloxy group. The foregoing groups canbe fully or partially halogenated with fluorine, chlorine, bromine, oriodine, or a combination comprising at least one of the foregoing. In anembodiment no halogens are present. Combinations of the foregoing Rgroups can be used in the same copolymer. In an embodiment, thepolysiloxane comprises R groups that have minimal hydrocarbon content.In a specific embodiment, an R group with a minimal hydrocarbon contentis a methyl group.

The average value of E in formula (9) can vary widely depending on thetype and relative amount of each component in the polycarbonatecomposition, whether the polymer is linear, branched or a graftcopolymer, the desired properties of the composition, and likeconsiderations. In an embodiment, E has an average value of 2 to 500, 2to 200, or 5 to 120, 10 to 100, 10 to 80, 2 to 30, or 30 to 80. In anembodiment E has an average value of 16 to 50, more specifically 20 to45, and even more specifically 25 to 45. In another embodiment, E has anaverage value of 4 to 50, 4 to 15, specifically 5 to 15, morespecifically 6 to 15, and still more specifically 7 to 10. In anembodiment, the polysiloxane units are structural units of formula (9a)

wherein E is as defined above; each R can independently be the same ordifferent, and is as defined above; and each Ar can independently be thesame or different, and is a substituted or unsubstituted C₆₋₃₀ compoundcontaining an aromatic group, wherein the bonds are directly connectedto the aromatic moiety. The Ar groups in formula (9a) can be derivedfrom a C₆₋₃₀ dihydroxy aromatic compound, for example a bisphenolcompound as described above or a monoaryl dihydroxy compound (6) above.Combinations comprising at least one of the foregoing dihydroxy aromaticcompounds can also be used. Exemplary dihydroxy aromatic compounds areresorcinol (i.e., 1,3-dihydroxybenzene), 4-methyl-1,3-dihydroxybenzene,5-methyl-1,3-dihydroxybenzene. 4,6-dimethyl-1,3-dihydroxvbenzene,1,4-dihydroxybenzene, 1,1-bis(4-hydroxyphenyl)methane,1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)propane,2,2-bis(4-hydroxyphenyl) butane. 2,2-bis(4-hydroxyphenyl) octane.1,1-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl) n-butane.2,2-bis(4-hydroxy-1-methylphenyl)propane,1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl sulfide), and1,1-bis(4-hydroxy-t-butylphenyl)propane. Combinations comprising atleast one of the foregoing dihydroxy compounds can also be used. In anembodiment, the dihydroxy aromatic compound is unsubstituted, or is doesnot contain non-aromatic hydrocarbyl substituents such as alkyl, alkoxy,or alkylene substituents.

In a specific embodiment, where Ar is derived from resorcinol, thepolysiloxane units are of the formula (9a-1)

or, where Ar is derived from bisphenol A, the polysiloxane has theformula (9a-2)

or a combination comprising at least one of the foregoing can be used,wherein E has an average value as described above, specifically anaverage value of 2 to 200.

In another embodiment, polydiorganosiloxane units are units of formula(9b)

wherein R and E are as described for formula (9), and each R² isindependently a divalent C₁₋₃₀ alkylene or C₇₋₃₀ arylene-alkylene. In aspecific embodiment, where R² is C₇₋₃₀ arylene-alkylene, thepolydiorganosiloxane units are of formula (9b-1)

wherein R and E are as defined for formula (9), and each R³ isindependently a divalent C₂₋₈ aliphatic group. Each M in formula (25)can be the same or different, and can be a halogen, cyano, nitro, C₁₋₈alkylthio, C₁₋₈ alkyl, C₁₋₈ alkoxy, C₂₋₈ alkenyl, C₂₋₈ alkenyloxy group,C₃₋₈ cycloalkyl, C₃₋₈ cycloalkoxy, C₆₋₁₀ aryl, C₆₋₁₀ aryloxy, C₇₋₁₂arylalkyl, C₇₋₁₂ arylalkoxy, C₇₋₁₂ alkylaryl, or C₇₋₁₂ alkylaryloxy,wherein each n is independently 0, 1, 2, 3, or 4. In an embodiment, M isbromo or chloro, an alkyl group such as methyl, ethyl, or propyl, analkoxy group such as methoxy, ethoxy, or propoxy, or an aryl group suchas phenyl, chlorophenyl, or tolyl; R³ is a dimethylene, trimethylene ortetramethylene group; and R is a C₁₋₈ alkyl, haloalkyl such astrifluoropropyl, cyanoalkyl, or aryl such as phenyl, chlorophenyl ortolyl. In another embodiment, R is methyl, or a combination of methyland trifluoropropyl, or a combination of methyl and phenyl. In stillanother embodiment, M is methoxy, n is 0 or 1, R³ is a divalent C₁₋₃aliphatic group, and R is methyl. The foregoing poly(carbonate-siloxane)copolymers can be manufactured by the methods described in U.S. Pat. No.6,072,011 to Hoover, for example.

In a specific embodiment, the polysiloxane units are eugenol-cappedpolysiloxane units of formula (9b-2)

where E has an average value as described above, specifically 2 to 200,2 to 100, 2 to 90, 2 to 80, or 2 to 30, 20 to 20, or 30 to 80. Inanother specific embodiment, the polysiloxane units are of formula(9b-3) or (9b-4)

where E has an average value as defined above, specifically an averagevalue of 2 to 200, 2 to 100, 2 to 90, 2 to 80, or 2 to 30, 20 to 20, or30 to 80.

The relative amount of carbonate units (1) and polysiloxane units (9) inthe PC-siloxane copolymers depends on the desired properties of thepolycarbonate composition, such as impact, smoke density, heat release,and melt viscosity. In particular the polycarbonate copolymer isselected to have an average value of E that provides good impact and/ortransparency properties, as well as to provide the desired weightpercent of siloxane units in the polycarbonate composition. For example,the polycarbonate copolymers can comprise siloxane units in an amount of0.1 to 60 weight percent (wt. %), specifically 0.5 to 55 wt. %, or 0.5to 45 wt. %, based on the total weight of the polymers in thepolycarbonate composition, with the proviso that the siloxane units areprovided by polysiloxane units covalently bonded in the polymer backboneof the polycarbonate copolymer.

A specific PC-siloxane comprises carbonate units (1) derived frombisphenol A, and second repeating siloxane units (9b-2). (9b-3), (9b-4),or a combination comprising at least one of the foregoing, specifically(9b-2). This polycarbonate copolymer can comprise the siloxane units inan amount of 0.1 to 60 weight percent (wt. %), 0.5 to 55 wt. %, 0.5 to45 wt. % 0.5 to 30 wt. %, or 0.5 to 20 wt. %, based on the total weightof the polycarbonate copolymer, with the proviso that the siloxane unitsare covalently bound to the polymer backbone of the polycarbonatecopolymer. In an embodiment, the remaining units are bisphenol units(1). Transparency can be achieved in this embodiment when E has anaverage value of 4 to 50, 4 to 15, specifically 5 to 15, morespecifically 6 to 15, and still more specifically 7 to 10. Thetransparent PC-siloxanes can be manufactured using one or both of thetube reactor processes described in U.S. Patent Application No.2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 maybe used to synthesize the poly(siloxane-carbonate) copolymers.

These and other methods for the manufacture of the PC-siloxanecopolymers are known. The PC-siloxane copolymers can have an intrinsicviscosity, as determined in chloroform at 25° C., of 0.3 to 1.5deciliters per gram (dlug), specifically 0.45 to 1.0 dLg. ThePC-siloxane copolymers can have a weight average molecular weight(M_(w)) of 10,000 to 100.000 g/mol, as measured by gel permeationchromatography (GPC) using a cross linked styrene-divinyl benzenecolumn, at a sample concentration of 1 milligram per milliliter, and ascalibrated with polycarbonate standards.

The addition of relatively small amount of PC-siloxane to the abovedescribed polycarbonate polymers reduces the smoke density DS-4 valuessignificantly. Similar improvements in DS-4 values can be achieved atthe same silicon content irrespective of the architecture of thePC-siloxane. Further, the length of the siloxane block does not have asignificant influence on the smoke density when compared at the samesilicon content in the polycarbonate composition. In an embodiment, thePC-siloxane is present in an amount effective to provide 0.1 to 1.00 wt.% of silicon based on the total weight of the composition.

In an embodiment, the low smoke polycarbonate compositions do notcontain or substantially free of any brominated polycarbonate. As usedherein, “substantially free of” refers to a composition containing lessthan 5 wt. %, specifically less than 1 wt. %, more specifically lessthan 0.1 wt. % of a brominated polycarbonate.

The polycarbonate compositions can include various other polymers toadjust the properties of the polycarbonate compositions, with theproviso that the other polymers are selected so as to not adverselyaffect the desired properties of the polycarbonate compositionsignificantly, in particular low smoke density and low heat release. Forexample, combination of a polycarbonate copolymer as described above anda homopolycarbonate having repeating units (1) such as a bisphenol Ahomopolycarbonate can still provide polycarbonate compositions havingthe required low smoke density. Other polymers include an impactmodifier such as natural rubber, fluoroelastomers, ethylene-propylenerubber (EPR), ethylene-butene rubber, ethylene-propylene-diene monomerrubber (EPDM), acrylate rubbers, hydrogenated nitrile rubber (HNBR)silicone elastomers, and elastomer-modified graft copolymers such asstyrene-butadiene-styrene (SBS), styrene-butadiene rubber (SBR),styrene-ethylene-butadiene-styrene (SEBS),acrylonitrile-butadiene-styrene (ABS),acrylonitrile-ethylene-propylene-diene-styrene (AES),styrene-isoprene-stvrene (SIS), methyl methacrylate-butadiene-styrene(MBS), high rubber graft (HRG), and the like can be present. In generalsuch other polymers provide less than 50 wt. %, less than 40 wt. %, lessthan 30 wt. %, less than 20 wt. %, or less than 10 wt. % of the totalcomposition. In an embodiment, no other polymers are present. In aspecific embodiment, no polymers containing halogen are present in thepolycarbonate compositions.

The polycarbonate compositions can include various additives ordinarilyincorporated into flame retardant compositions having low smoke densityand low heat release, with the proviso that the additive(s) are selectedso as to not adversely affect the desired properties of thepolycarbonate composition significantly, in particular low smoke densityand low heat release. Such additives can be mixed at a suitable timeduring the mixing of the components for forming the composition.Exemplary additives include fillers, reinforcing agents, antioxidants,heat stabilizers, light stabilizers, ultraviolet (UV) light stabilizers,plasticizers, lubricants, mold release agents, antistatic agents,colorants such as such as titanium dioxide, carbon black, and organicdyes, surface effect additives, light diffuser additives, radiationstabilizers, additional flame retardants, and anti-drip agents. Acombination of additives can be used. In general, the additives are usedin the amounts generally known to be effective. The total amount ofadditives (other than any filler or reinforcing agents) is generally0.01 to 25 parts per hundred parts by the total weight of the polymersin the composition (PHR).

Examples of inorganic pigments are white pigments such as titaniumdioxide in its three modifications of rutile, anatase or brookite, leadwhite, zinc white, zinc sulfide or lithopones; black pigments such ascarbon black, black iron oxide, iron manganese black or spinel black;chromatic pigments such as chromium oxide, chromium oxide hydrate green,cobalt green or ultramarine green, cobalt blue, iron blue, Milori blue,ultramarine blue or manganese blue, ultramarine violet or cobalt andmanganese violet, red iron oxide, cadmium sulfoselenide, molybdate redor ultramarine red; brown iron oxide, mixed brown, spinel phases andcorundum phases or chromium orange; yellow iron oxide, nickel titaniumyellow, chromium titanium yellow, cadmium sulfide, cadmium zinc sulfide,chromium yellow, zinc yellow, alkaline earth metal chromates, Naplesyellow; bismuth vanadate, and effect pigments such as interferencepigments and luster pigments. Other specific inorganic pigments includePigment White 6, Pigment White 7, Pigment Black 7, Pigment Black 11,Pigment Black 22, Pigment Black 27/30, Pigment Yellow 34, Pigment Yellow35/37, Pigment Yellow 42, Pigment Yellow 53, Pigment Brown 24, PigmentYellow 119, Pigment Yellow 184, Pigment Orange 20, Pigment Orange 75,Pigment Brown 6, Pigment Brown 29, Pigment Brown 31, Pigment Yellow 164,Pigment Red 101, Pigment Red 104, Pigment Red 108, Pigment Red 265,Pigment Violet 15, Pigment Blue 28/36, Pigment Blue 29, Pigment Green17, and Pigment Green 26/50. A combination comprising at least one ofthe foregoing pigments can be used.

Exemplary dyes are generally organic materials and include coumarin dyessuch as coumarin 460 (blue), coumarin 6 (green), nile red or the like;lanthanide complexes; hydrocarbon and substituted hydrocarbon dyes;polycyclic aromatic hydrocarbon dyes; scintillation dyes such as oxazoleor oxadiazole dyes; aryl- or heteroaryl-substituted poly (C₂₋₈) olefindyes; carbocyanine dyes; indanthrone dyes; phthalocyanine dyes; oxazinedyes; carbostyryl dyes; napthalenetetracarboxylic acid dyes; porphyrindyes; bis(styryl)biphenyl dyes; acridine dyes; anthraquinone dyes;cyanine dyes; methine dyes; arylmethane dyes; azo dyes; indigoid dyes,thioindigoid dyes, diazonium dyes; nitro dyes; quinone imine dyes;aminoketone dyes; tetrazolium dyes; thiazole dyes; perylene dyes,perinone dyes; bis-benzoxazolylthiophene (BBOT); triarylmethane dyes;xanthene dyes; thioxanthene dyes; naphthalimide dyes; lactone dyes;fluorophores such as anti-stokes shift dyes which absorb in the nearinfrared wavelength and emit in the visible wavelength, or the like;luminescent dyes such as 7-amino-4-methylcoumarin;3-(2′-benzothiazolyl)-7-diethylaminocoumarin;2-(4-biphenylyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole;2,5-bis-(4-biphenylyl)-oxazole; 2,2′-dimethyl-p-quaterphenyl;2,2-dimethyl-p-terphenyl; 3,5,3″″,5″″-tetra-t-butyl-p-quinquephenyl;2,5-diphenylfuran; 2,5-diphenyloxazole; 4,4′-diphenylstilbene;4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran;1,1′-diethyl-2,2′-carbocyanine iodide;3,3′-diethyl-4,4′,5,5′-dibenzothiatricarbocyanine iodide;7-dimethylamino-1-methyl-4-methoxy-8-azaquinolone-2;7-dimethylamino-4-methylquinolone-2;2-(4-(4-dimethylaminophenyl)-1,3-butadienyl)-3-ethylbenzothiazoliumperchlorate; 3-diethylamino-7-diethyliminophenoxazonium perchlorate;2-(1-naphthyl)-5-phenyloxazole; 2,2′-p-phenylen-bis(5-phenyloxazole);rhodamine 700; rhodamine 800; pyrene, chrysene, rubrene, coronene, orthe like; or combinations comprising at least one of the foregoing dyes.Dyes can be used in amounts of 0.001 to 5 PHR.

The use of pigments such as titanium dioxide produces whitecompositions, which are commercially desirable. It has surprisingly beenfound that the use of titanium dioxide can further improve smoke densityand/or heat release properties. Pigments such as titanium dioxide (orother mineral fillers) can be present in the polycarbonate compositionsin amounts of 0 to 12 wt. %, 0.1 to 12 wt. %, 0.1 to 9 wt. %, 0.5 to 5wt. %, or 0.5 to 3 wt. %, each based on the total weight of thecomposition.

Compositions used to form light-diffusive articles, for examplelight-diffusive train components, can further comprise a light diffuseradditive, i.e., a plurality of light-diffusive particles to provide thelight-diffusive effect. Such particles are generally insoluble in thepolymers of the thermoplastic compositions. Light-diffuser additivesinclude silicone particles, e.g., polymethylsilsesquioxanes availablefrom GE Silicones under the trade name Tospearl*, crosslinkedpoly(methyl methacrylate) (PMMA) and other organic polymer particles,e.g., methyl methacrylate/ethyleneglycol dimethacrylate copolymersavailable from Sekisui Plastics Co. under the trade name TECHPOLYMERMBS*, and low levels of TiO₂. A combination comprising at least one ofthe foregoing types of light diffuser additives can be used. Suchdiffuser particles can be added to high clarity or medium claritycompositions to provide light-diffusive compositions, for example in anamount of 0.05 to 10.0 wt. %, 0.2 to 8.0 wt. %, 0.5 to 6.0 wt. %, or 0.5to 5.00 wt. % of the light diffuser additive, based on the total weightof the polymers in the in the thermoplastic compositions. In general,greater amounts of light diffuser additive is used in the manufacture ofthinner articles to obtain the same degree of light diffusion. In anembodiment the light diffuser additives are silicone particles. Thelight diffuser additives can also be PMMA. Likewise, the light diffuseradditives can be a combination of silicone particles and PMMA particles.

Exemplary antioxidant additives include organophosphites such astris(nonyl phenyl)phosphite, tris(2,4-di-t-butylphenyl)phosphite,bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, distearylpentaerythritol diphosphite; alkylated monophenols or polyphenols;alkylated reaction products of polyphenols with dienes, such astetrakis[methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)]methane;butylated reaction products of para-cresol or dicyclopentadiene;alkylated hydroquinones; hydroxylated thiodiphenyl ethers;alkylidene-bisphenols; benzyl compounds; esters ofbeta-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid with monohydricor polyhydric alcohols; esters ofbeta-(5-tert-butyl-4-hydroxy-3-methylphenyl)-propionic acid withmonohydric or polyhydric alcohols; esters of thioalkyl or thioarylcompounds such as distearylthiopropionate, dilaurylthiopropionate,ditridecylthiodipropionate,octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate,pentaerythrityl-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate;amides of beta-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid, orcombinations comprising at least one of the foregoing antioxidants.Antioxidants are used in amounts of 0.01 to 0.1 PHR

Exemplary heat stabilizer additives include organophosphites such astriphenyl phosphite, tris-(2,6-dimethylphenyl)phosphite, and tris-(mixedmono- and di-nonylphenyl)phosphite; phosphonates such as dimethylbenzenephosphonate, phosphates such as trimethyl phosphate; or combinationscomprising at least one of the foregoing heat stabilizers. Heatstabilizers are used in amounts of 0.01 to 0.1 PHR.

Light stabilizers and/or ultraviolet light (UV) absorbing additives canalso be used. Exemplary light stabilizer additives includebenzotriazoles such as 2-(2-hydroxy-5-methylphenyl)benzotriazole,2-(2-hydroxy-5-tert-octylphenyl)-benzotriazole and 2-hydroxy-4-n-octoxybenzophenone, or combinations comprising at least one of the foregoinglight stabilizers. Light stabilizers are used in amounts of 0.01 to 5PHR.

Exemplary UV absorbing additives include hydroxybenzophenones;hydroxybenzotriazoles; hydroxybenzotriazines; cyanoacrylates;oxanilides; benzoxazinones;2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)-phenol (CYASORB®5411); 2-hvdroxy-4-n-octyloxvbenzophenone (CYASORB® 531);2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-(octyloxy)-phenol(CYASORB® 1164); 2,2′-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one)(CYASORB® UV-3638);1,3-bis[(2-cyano-3,3-diphenylacryloyl)oxy]-2,2-bis[[(2-cyano-3,3-diphenylacryloyl)oxy]methyl]propane(UVINUL® 3030); 2,2′-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one);1,3-bis[(2-cyano-3,3-diphenylacrylovyl)oxy]-2,2-bis[[(2-cyano-3,3-diphenylacryloyl)oxy]methyl]propane;nano-size inorganic materials such as titanium oxide, cerium oxide, andzinc oxide, all with particle size less than or equal to 100 nanometers;or combinations comprising at least one of the foregoing UV absorbers.UV absorbers are used in amounts of 0.01 to 5 PHR.

Plasticizers, lubricants, and/or mold release agents can also be used.There is considerable overlap among these types of materials, whichinclude phthalic acid esters such asdioctyl-4,5-epoxy-hexahydrophthalate;tris-(octoxycarbonylethyl)isocyanurate; tristearin: poly-alpha-olefins;epoxidized soybean oil; silicones, including silicone oils; esters, forexample, fatty acid esters such as alkyl stearyl esters. e.g., methylstearate, stearyl stearate, pentaerythritol tetrastearate, and the like;combinations of methyl stearate and hydrophilic and hydrophobic nonionicsurfactants comprising polyethylene glycol polymers, polypropyleneglycol polymers, poly(ethylene glycol-co-propylene glycol) copolymers,or a combination comprising at least one of the foregoing glycolpolymers, e.g., methyl stearate and polyethylene-polypropylene glycolcopolymer in a solvent; waxes such as beeswax, montan wax, and paraffinwax. Such materials are used in amounts of 0.1 to 1 PHR.

Flame retardant salts are not needed to obtain the desired low smoke andlow heat release properties. Examples of flame retardant salts includeof C₁₋₁₆ alkyl sulfonate salts such as potassium perfluorobutanesulfonate (Rimar salt), potassium perfluorooctane sulfonate,tetraethylammonium perfluorohexane sulfonate, and potassiumdiphenylsulfone sulfonate (KSS); salts such as Na₂CO₃, K₂CO₃, MgCO₃,CaCO₃, and BaCO₃, phosphate salts, or fluoro-anion complexes such asLi₃AlF₆, BaSiF₆, KBF₄, K₃AlF₆, KAlF₄, K₂SiF₆, and/or Na₃AlF₆. In anembodiment, no flame retardant salts are present. When present, flameretardant salts are present in amounts of 0.01 to 10 PHR, morespecifically 0.02 to 1 PHR.

Organic flame retardants can be present, for example organic compoundsthat include phosphorus, nitrogen, bromine, and/or chlorine. However,halogenated flame retardants are generally avoided, such that thepolycarbonate composition can be essentially free of chlorine andbromine. “Essentially free of chlorine and bromine” as used herein meanshaving a bromine and/or chlorine content of less than or equal to 100parts per million by weight (ppm), less than or equal to 75 ppm, or lessthan or equal to 50 ppm, based on the total parts by weight of thecomposition, excluding any filler.

The polycarbonate compositions further comprise an organophosphorusflame retardant in an amount effective to provide 0.1 to 2.0 wt. %phosphorus, based on the weight of the composition. For example, theorganophosphorus compound, specifically BPADP or RDP can be present inan amount of 2 to 20 wt. %, which is effective to provide 0.1 to 2.0 wt.% of phosphorus based on the total weight of the composition. Inventorshave found that the presence of certain organophosphorus flameretardants for example BPADP, has a positive effect on the smoke densityas it further reduced DS-values of a composition containing apolycarbonate polymer and a second polymer, but not the flame retardant.Further, it was found that these flame retardants have a positive effecton MAHRE, as they reduce MAHRE of a composition containing apolycarbonate polymer and a second polymer but not the organophosphoruscomponent. Further, certain organophosphorus flame retardants improvethe melt flow while at the same time maintain ductility even atrelatively high loading levels.

Organophosphorus compounds include aromatic organophosphorus compoundshaving at least one organic aromatic group and at least onephosphorus-containing group, as well as organic compounds having atleast one phosphorus-nitrogen bond.

In the aromatic organophosphorus compounds that have at least oneorganic aromatic group, the aromatic group can be a substituted orunsubstituted C₃₋₃₀ group containing one or more of a monocyclic orpolycyclic aromatic moiety (which can optionally contain with up tothree heteroatoms (N, O, P, S, or Si)) and optionally further containingone or more nonaromatic moieties, for example alkyl, alkenyl, alkynyl,or cycloalkyl. The aromatic moiety of the aromatic group can be directlybonded to the phosphorus-containing group, or bonded via another moiety,for example an alkylene group. The aromatic moiety of the aromatic groupcan be directly bonded to the phosphorus-containing group, or bonded viaanother moiety, for example an alkylene group. In an embodiment thearomatic group is the same as an aromatic group of the polycarbonatebackbone, such as a bisphenol group (e.g., bisphenol A), a monoarylenegroup (e.g., a 1,3-phenylene or a 1,4-phenylene), or a combinationcomprising at least one of the foregoing.

The phosphorus-containing group can be a phosphate (P(═O)(OR)₃),phosphite (P(OR)₃), phosphonate (RP(═O)(OR)₂), phosphinate(R₂P(═O)(OR)), phosphine oxide (R₃P(═O)), or phosphine (R₃P), whereineach R in the foregoing phosphorus-containing groups can be the same ordifferent, provided that at least one R is an aromatic group. Acombination of different phosphorus-containing groups can be used. Thearomatic group can be directly or indirectly bonded to the phosphorus,or to an oxygen of the phosphorus-containing group (i.e., an ester).

In an embodiment the aromatic organophosphorus compound is a monomericphosphate. Representative monomeric aromatic phosphates are of theformula (GO)₃P═O, wherein each G is independently an alkyl, cycloalkyl,aryl, alkylarylene, or arylalkylene group having up to 30 carbon atoms,provided that at least one G is an aromatic group. Two of the G groupscan be joined together to provide a cyclic group. In some embodiments Gcorresponds to a monomer used to form the polycarbonate, e.g.,resorcinol. Exemplary phosphates include phenyl bis(dodecyl)phosphate,phenyl bis(neopentyl)phosphate, phenylbis(3,5,5′-trimethylhexyl)phosphate, ethyl diphenyl phosphate,2-ethylhexyl di(p-tolyl)phosphate, bis(2-ethylhexyl) p-tolyl phosphate,tritolyl phosphate, bis(2-ethylhexyl) phenyl phosphate,tri(nonylphenyl)phosphate, bis(dodecyl) p-tolyl phosphate, dibutylphenyl phosphate, 2-chloroethyl diphenyl phosphate, p-tolylbis(2,5,5′-trimethylhexyl)phosphate, 2-ethylhexyl diphenyl phosphate,and the like. A specific aromatic phosphate is one in which each G isaromatic, for example, triphenyl phosphate, tricresyl phosphate,isopropylated triphenyl phosphate, and the like.

Di- or polyfunctional aromatic phosphorus-containing compounds are alsouseful, for example, compounds of formula (14)

wherein each G² is independently a hydrocarbon or hydrocarbonoxy having1 to 30 carbon atoms. In some embodiments G corresponds to a monomerused to form the polycarbonate, e.g., resorcinol.

Specific aromatic organophosphorus compounds have two or morephosphorus-containing groups, and are inclusive of acid esters offormula (15)

wherein R¹⁶, R¹⁷, R¹⁸, and R¹⁹ are each independently C₁₋₈ alkyl, C₅₋₆cycloalkyl, C₆₋₂₀ aryl, or C₇₋₁₂ arylalkylene, each optionallysubstituted by C₁₋₁₂ alkyl, specifically by C₁₋₄ alkyl and X is a mono-or poly-nuclear aromatic C₆₋₃₀ moiety or a linear or branched C₂₋₃₀aliphatic radical, which can be OH-substituted and can contain up to 8ether bonds, provided that at least one of R¹⁶, R¹⁷, R¹⁸, R¹⁹, and X isan aromatic group. In some embodiments R¹⁶, R¹⁷, R¹⁸, and R¹⁹ are eachindependently C₁₋₄ alkyl, naphthyl, phenyl(C₁₋₄)alkylene, or aryl groupsoptionally substituted by C₁₋₄ alkyl. Specific aryl moieties are cresyl,phenyl, xylenyl, propylphenyl, or butylphenyl. In some embodiments X informula (15) is a mono- or poly-nuclear aromatic C₆₋₃₀ moiety derivedfrom a diphenol. Further in formula (15), n is each independently 0 or1; in some embodiments n is equal to 1. Also in formula (15), q is from0.5 to 30, from 0.8 to 15, from 1 to 5, or from 1 to 2. Specifically. Xcan be represented by the following divalent groups (16), or acombination comprising one or more of these divalent groups.

In these embodiments, each of R¹⁶, R¹⁷, R¹⁸, and R¹⁹ can be aromatic,i.e., phenyl, n is 1, and p is 1-5, specifically 1-2. In someembodiments at least one of R¹⁶, R¹⁷, R¹⁸, R¹⁹, and X corresponds to amonomer used to form the polycarbonate, e.g., bisphenol A or resorcinol.In another embodiment, X is derived especially from resorcinol,hydroquinone, bisphenol A, or diphenylphenol, and R¹⁶, R¹⁷, R¹⁸, R¹⁹, isaromatic, specifically phenyl. A specific aromatic organophosphoruscompound of this type is resorcinol bis(diphenyl phosphate), also knownas RDP. Another specific class of aromatic organophosphorus compoundshaving two or more phosphorus-containing groups are compounds of formula(17)

wherein R¹⁶, R¹⁷, R¹⁸, R¹⁹, n, and q are as defined for formula (19) andwherein Z is C₁₋₇ alkylidene. C₁₋₇ alkylene, C₅₋₁₂ cycloalkylidene, —O—,—S—, —SO₂—, or —CO—, specifically isopropylidene. A specific aromaticorganophosphorus compound of this type is bisphenol A bis(diphenylphosphate), also known as BPADP, wherein R¹⁶, R¹⁷, R¹⁸, and R¹⁹ are eachphenyl, each n is 1, and q is from 1 to 5, from 1 to 2, or 1.

Organophosphorus compounds containing at least one phosphorus-nitrogenbond includes phosphazenes, phosphorus ester amides, phosphoric acidamides, phosphonic acid amides, phosphinic acid amides, andtris(aziridinyl) phosphine oxide. Phosphazenes (18) and cyclicphosphazenes (19)

in particular can used, wherein w1 is 3 to 10,000 and w2 is 3 to 25,specifically 3 to 7, and each R^(w) is independently a C₁₋₁₂ alkyl,alkenyl, alkoxy, aryl, aryloxy, or polyoxyalkylene group. In theforegoing groups at least one hydrogen atom of these groups can besubstituted with a group having an N, S, O, or F atom, or an aminogroup. For example, each R^(w) can be a substituted or unsubstitutedphenoxy, an amino, or a polyoxyalkylene group. Any given R^(w) canfurther be a crosslink to another phosphazene group. Exemplarycrosslinks include bisphenol groups, for example bisphenol A groups.Examples include phenoxy cyclotriphosphazene, octaphenoxycyclotetraphosphazene decaphenoxy cyclopentaphosphazene, and the like. Acombination of different phosphazenes can be used. A number ofphosphazenes and their synthesis are described in H. R. Allcook,“Phosphorus-Nitrogen Compounds” Academic Press (1972), and J. E. Mark etal., “Inorganic Polymers” Prentice-Hall International, Inc. (1992).

Accordingly, depending on the particular organophosphorus compound used,the polycarbonate compositions can comprise from 0.3 to 20 wt. %, or 0.5to 15 wt. %, or 3.5 to 12 wt. % of the organophosphorus flame retardant,each based on the total weight of the composition. Specifically, theorganophosphorus compounds can be bisphenol A bis(diphenyl phosphate),triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresylphosphate, or a combination comprising at least one of the foregoing.

Anti-drip agents in most embodiments are not used in the polycarbonatecompositions. Anti-drip agents include a fibril-forming or non-fibrilforming fluoropolymer such as polytetrafluoroethylene (PTFE). Theanti-drip agent can be encapsulated by a rigid copolymer, for examplestyrene-acrylonitrile copolymer (SAN). PTFE encapsulated in SAN is knownas TSAN. Antidrip agents are substantially absent or completely absentfrom the polycarbonate compositions in some embodiments.

Methods for forming the polycarbonate compositions can vary. In anembodiment, the polymers are combined (e.g., blended) with any additives(e.g., a mold release agent) such as in a screw-type extruder. Thepolymers any additives can be combined in any order, and in form, forexample, powder, granular, filamentous, as a masterbatch, and the like.The polycarbonate compositions can be foamed, extruded into a sheet, oroptionally pelletized. Methods of foaming a polycarbonate compositionusing frothing or physical or chemical blowing agents are known and canbe used. The pellets can be used for molding into articles, foaming, orthey can be used in forming a sheet of the flame retardant polycarbonatecomposition. In some embodiments, the composition can be extruded (orco-extruded with a coating or other layer) in the form of a sheet and/orcan be processed through calendaring rolls to form the desired sheet.

As discussed above, the polycarbonate compositions are formulated tomeet strict low smoke density requirements. The relative amounts ofpolycarbonate polymer and the second polymer in the polycarbonatecompositions depends on the particular polycarbonate polymer and thesecond polymer used, the targeted level of smoke density and heatrelease, and other desired properties of the polycarbonate composition,such as transparency, haze, impact strength and flow. In an embodiment,the second polymer is present in an amount effective to provide 0.10 to1.00 wt. % silicon based on the total weight of the composition, andwithin this range the specific amount is selected to be effective toprovide a smoke density (Ds-4) of less than 300, or of less than 250, orof less than 200 measured according to ISO 5659-2 on a 3 mm thick plaqueat 50 kW % m². These values can be obtained in articles having a widerange of thicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm.

The polycarbonate compositions can further have a maximum average rateof heat emission (MAHRE) of 90 kW/m² or less, or 80 kW/m² or less, or 70kW/m² or less as measured according to ISO 5660-1 on a 3 mm thick plaqueat 50 kW/m².

Use of a PC-siloxane, a polydialkylsiloxane, or a combination of aPC-siloxane and a polydialkylsiloxane and an organophosphorus compoundin an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, basedon the total weight of the thermoplastic polymer composition can lowersmoke density (Ds-4) of polycarbonate polymers to the desired levels.For example, polycarbonate polymers such as PPP-BPIBPA or PPC havelimited inherent smoke and heat release properties, a combination ofthese polycarbonate polymers with a PC-siloxane such as (bisphenol Acarbonate)-co-(polydimethylsiloxane) has positive effect on the smokedensity (Ds-4) measured according to ISO5659-2 on a 3 mm thick plaque at50 kW/m², such that these compositions are suitable for EN-45545 typeapplications (R6 applications qualifying for HL2 compliance, a smokedensity (Ds-4) at or below 300 is required at 50 kW/m²), provided thatthe other required properties (e.g. heat release) meet the selectioncriteria as well.

Thus, in some embodiments the compositions can have a MAHRE of 90 kW/m²or less as measured according to ISO 5660-1 on a 3 mm thick plaque at 50kW/m², a Ds-4 smoke density of 300 or less as measured according to ISO5659-2 on a 3 mm thick plaque at 50 kW/m², measured according toresulting in R6 applications in compliance with Hazard Level 2 ratingfor the EN45545 (2013) standard. These values can be obtained inarticles having a wide range of thicknesses, for example from 0.1 to 10mm, or 0.5 to 5 mm.

The compositions can also have a critical heat flux at extinguishment(CFE) at or above 20 kW/m², at or above 22 kW/m², or at or above 24kW/m² measured according to ISO 5658-2 on a 3 mm thick plaque.

Thus, in some embodiments the compositions can have a MAHRE of 90 kW/m²or less as measured according to ISO 5660-1 on a 3 mm thick plaque at 50kW/m², a Ds-4 smoke density of 300 or less as measured according to ISO5659-2 on a 3 mm thick plaque at 50 kW/m², and a critical heat flux atextinguishment (CFE) at or above 20 kW/m² measured according to ISO5658-2 on a 3 mm thick plaque, resulting in R1 applications incompliance with Hazard Level 2 rating for the EN45545 (2013) standard.These values can be obtained in articles having a wide range ofthicknesses, for example from 0.1 to 10 mm, or 0.5 to 5 mm.

The polycarbonate compositions can be formulated to have lowerdensities, in particular a density of 1.35 g/cc or less, 1.34 g/cc orless, 1.33 g/cc or less, 1.32 g/cc or less, 1.31 g/cc or less, 1.30 g/ccor less, or 1.29 g/cc or less. The same or similar values can beobtained in components having a wide range of thicknesses, for examplefrom 0.1 to 10 mm, or 0.5 to 5 mm.

The polycarbonate compositions can further have good melt viscosities,which aid processing. The polycarbonate compositions can have a meltvolume flow rate (MVR, cubic centimeter per 10 minutes (cc/10 min) of 4to about 30, greater than or equal to 5, greater than or equal to 6,greater than or equal to 7, greater than or equal to 8, greater than orequal to 9, greater than or equal to 10, greater than or equal to 12, orgreater than or equal to 14 cc/min. measured at 300° C./1.2 Kg at 360second dwell according to ISO 1133. The same or similar values can beobtained in articles having a wide range of thicknesses, for examplefrom 0.1 to 10 mm, or 0.5 to 5 mm.

The polycarbonate compositions can further have excellent impactproperties, in particular multiaxial impact (MAI) and ductility. Thecompositions can have an MAI equal to or higher than 1(00) J, measuredat 23° C. at an impact speed of 4.4 m/second according to ISO 6603 ondiscs with a thickness of 3.2 mm. The compositions can have a ductilityin multiaxial impact of 80% and higher, specifically 100%, measured at23° C. at an impact speed of 4.4 m/second according to ISO 6603 on discswith a thickness of 3.2 mm. These values can be obtained in articleshaving a wide range of thicknesses, for example from 0.1 to 10 mm, or0.5 to 5 mm. In some embodiments, the composition can have an MAI equalto or higher than 100 J and a high ductility (80% or greater, forexample 100%) at lower temperatures such as 10° C., 0° C., −10° C., −20°C. and −30° C.

As noted above the present discovery allows the manufacture ofcompositions have very low smoke densities (Ds-4), measured according toISO5659-2 on a 3 mm thick plaque at 50 kW/m², and low heat release(MAHRE) measured according to ISO 5660-1 on a 3 mm thick plaque at 50kW/m², while maintaining the advantageous properties of polycarbonates.Thus, polycarbonate compositions having practical impact propertieswithin 20%, within 10%, within 5%, or within 1% of the same compositionswithout the PC-siloxane or polydialkylsiloxane can be manufactured. Forexample, the polycarbonate compositions can have an MAI within 20%,within 10%, within 5%, or within 1% of the MAI of the same composition,each measured at 23° C. at an impact speed of 4.4 m/second according toISO 6603 on discs with a thickness of 3.2 mm. The transmission propertyof the polycarbonate polymers can further be maintained in someembodiments.

Transportation components, in particular seat components and claddingsfor train interiors that are molded or extruded from the thermoplasticcompositions are also provided. Molding can be by a variety of meanssuch as injection molding, rotational molding, blow molding, and thelike. In an embodiment, the molding is by injection molding.Illustrative claddings include, for example interior vertical surfaces,such as side walls, front walls, end-walls, partitions, room dividers,flaps, boxes, hoods and louvres: interior doors and linings for internaland external doors; window insulations, kitchen interior surfaces,interior horizontal surfaces, such as ceiling paneling, flaps, boxes,hoods and louvres; luggage storage areas, such as overhead and verticalluggage racks, luggage containers and compartments; driver's deskapplications, such as paneling and surfaces of driver's desk; interiorsurfaces of gangways, such as interior sides of gangway membranes(bellows) and interior linings; window frames (including sealants andgaskets); (folding) tables with downward facing surface; interior andexterior surface of air ducts, and devices for passenger information(such as information display screens) and the like.

In an embodiment, the seat components and claddings meet certaincriteria set forth in European Railway standard EN-45545 (2013). TheEuropean Union has approved the introduction of a set of fire testingstandards for the railroad industry that prescribes certainflammability, flame spread rate, heat release, smoke emission, and smoketoxicity requirements for materials used in railway vehicles, known asEuropean Railway standard EN-45545 (2013). Based on the vehiclematerial, end-use, and fire risks, 26 different “Requirement” categoriesfor materials have been established (R1-R26). Seat components such as aback or base shell fall under the R6 application type. Lighting stripsfall under the R3 application type. The R1 application type covers,amongst others, interior vertical surfaces, such as side walls, frontwalls, end-walls, partitions, room dividers, flaps, boxes, hoods andlouvres; interior doors and linings for internal and external doors;window insulations, kitchen interior surfaces, interior horizontalsurfaces, such as ceiling paneling, flaps, boxes, hoods and louvres;luggage storage areas, such as overhead and vertical luggage racks,luggage containers and compartments; driver's desk applications, such aspaneling and surfaces of driver's desk; interior surfaces of gangways,such as interior sides of gangway membranes (bellows) and interiorlinings; window frames (including sealants and gaskets): (folding)tables with downward facing surface; interior and exterior surface ofair ducts, and devices for passenger information (such as informationdisplay screens) and the like.

“Hazard Levels” (HL1 to HL3) have been designated, reflecting the degreeof probability of personal injury as the result of a fire. The levelsare based on dwell time and are related to operation and designcategories. HL1 is the lowest hazard level and is typically applicableto vehicles that run under relatively safe conditions (easy evacuationof the vehicle). HL3 is the highest hazard level and represents mostdangerous operation/design categories (difficult and/or time-consumingevacuation of the vehicle, e.g. in underground rail cars). For eachapplication type, different test requirements for the hazard levels aredefined. The testing methods, and smoke density and maximum heat releaserate values for the various hazard levels in the European Railwaystandard EN-45545 (2013) are shown in Table 1A for R6 applications.

TABLE 1A European Railways Standard EN 45545 for R6 applications SmokeDensity, Heat release, DS-4 ISO MAHRE (kW/m²) 5659-2 at 50 ISO 5660-1 at50 Hazard Level kW/m² kW/m² HL1 ≦600 — HL2 ≦300 ≦90 HL3 ≦150 ≦60

The testing methods, and smoke density, maximum heat release rate valuesand critical heat flux at extinguishment for the various hazard levelsin the European Railway standard EN-45545 (2013) are shown in Table 1Bfor R1 applications.

TABLE 1B European Railways Standard EN 45545 for R1 applicationsCritical heat flux at extin- Smoke Density, Heat release, guishment DS-4ISO MAHRE (kW/m²) (CFE) 5659-2 at 50 ISO 5660-1 at 50 [kW/m²] HazardLevel kW/m² kW/m² ISO 5658-2 HL1 ≦600 — >20 HL2 ≦300 ≦90 >20 HL3 ≦150≦60 >20

Data in the Examples shows that the compositions herein can meet therequirements for HL2, for both R1 and R6 applications.

While the compositions described herein are designed for usespecifically in railway interiors, it is to be understood that thecompositions are also useful in other interior components that arerequired to meet the test standards for HL2 for both R1 and R6applications. Interior bus components are specifically mentioned.Current discussions directed to increasing bus safety include proposalsto apply the HL2 standards to interior bus components. This inventionaccordingly includes interior bus components, including seat componentsand claddings as described above and comprising the specificcompositions described herein, and particularly below, that meet thetests specified in the HL2 standards described above.

In an embodiment, provided herein is an a railway component wherein thecomponent is a seat component, and wherein the railway component ismolded or formed from a thermoplastic polymer composition comprising 50to 93 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalateester) (for example, comprising 75 to 85 wt. % of the ester units,wherein the ester units have a molar ratio of isophthalate toterephthalate of 98:2 to 88:12, or comprising 35 to 45 wt. % ofcarbonate units and 55 to 65 wt. % of ester units, wherein the esterunits have a molar ratio of isophthalate to terephthalate of 45:55 to55:45); 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenolA carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing (specificallyof formula 9b-2), wherein E has an average value of 2 to 200 (or 2 to60, or 2 to 30), wherein the poly(carbonate-siloxane) comprises 0.5 to55 wt. % of siloxane units based on the total weight of thepoly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compoundin an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, basedon the total weight of the thermoplastic polymer composition; andoptionally, up to 5 wt. % of an additive selected from a processing aid,a heat stabilizer, an ultra violet light absorber, a colorant, or acombination comprising at least one of the foregoing; wherein an articlehaving a thickness of 0.5 to 10 mm molded from the composition has aDs-4 smoke density of less than or equal to 300 measured according toISO 5659-2 on a 3 mm thick plaque at 50 kW/m², and a MAHRE of less thanor equal to 90 kW/m² measured according to ISO 5660-1 on a 3 mm thickplaque at 50 kW/m², a multiaxial impact energy at or above 100 J and aductility of 80 to 100%, measured at +23° C. at an impact speed of 4.4m/second according to ISO 6603 on 3.2 mm thick discs, optionally amolded or formed sample of the thermoplastic polymer composition has atransmission of 80% or more or a haze of 5 or less, each measured usingthe color space CIE1931 (Illuminant C and a 2° observer) at a thicknessof 3 mm according to ASTM D1003, and optionally, a melt volume flow rateof greater than 4 cc/10 min measured at 300° C. under 1.2 kg forcemeasured according to ISO 1133. Optionally, the seat component isinjection molded, and the thermoplastic composition has a melt volumeflow rate of equal to or greater than 4 cc/10 min measured at 300° C.under 1.2 kg force measured according to ISO 1133; or the seat componentis extruded, and the thermoplastic composition has a Vicat B120 of lessthan 160° C. measured according to ISO 306.

In a specific embodiment, the foregoing composition comprises 4 to 20wt. % of the poly(carbonate-siloxane) having 1 to 10 mol % of siloxaneunits, and a molded or formed sample of the thermoplastic polymercomposition has a transmission of greater than 80% or a haze of 5 orless, measured according to ASTM D1003 using the color space CIE1931(Illuminant C and a 2° observer) at a thickness of 3 mm. Thesetransparencies can be achieved by use of a PC-siloxane comprisingcarbonate units (1) derived from bisphenol A, and repeating siloxaneunits (9b-2). (9b-3), (9b-4), or a combination comprising at least oneof the foregoing (specifically of formula 9b-2), wherein E has anaverage value of 4 to 50, 4 to 15, specifically 5 to 15, morespecifically 6 to 15, and still more specifically 7 to 10. Thetransparent PC-siloxanes can be manufactured using one or both of thetube reactor processes described in U.S. Patent Application No.2004/0039145A1 or the process described in U.S. Pat. No. 6,723,864 maybe used to synthesize the poly(siloxane-carbonate) copolymers.

In other specific embodiments of the foregoing seat components, one ormore of the following conditions can apply; the thermoplasticcomposition can further comprise 5 to 20 wt. % of a bisphenol Apolycarbonate; the organophosphorus compound can be an aromaticorganophosphorus compound can have at least one organic aromatic groupand at least one phosphorus-containing group, such as bisphenol Abis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenylphosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or acombination comprising at least one of the foregoing, or an organiccompound having at least one phosphorus-nitrogen bond such as aphosphazene, phosphorus ester amide, phosphoric acid amide, phosphonicacid amide, phosphinic acid amide, tris(aziridinyl) phosphine oxide, ora combination comprising at least one of the foregoing; optionally, thecomposition comprises 0.05 to 10.0 wt. % of a light diffuser additivecomprising silicone, polymethylsilsesquioxane, crosslinked poly(methylmethacrylate), methyl methacrylate/ethyleneglycol dimethacrylatecopolymer, TiO₂, or a combination comprising at least one of theforegoing, based on the total weight of the polymers in thethermoplastic composition, or 0.00002 to 5.0 wt. % of one or morecolorants based on the total weight of the polymers in the thermoplasticcomposition; or no or substantially no flame retarding brominatedcompounds, flame retardant salts, or a combination comprising at leastone of the foregoing are present in the thermoplastic composition.

Also provided herein is a railway component wherein the component is aseat component, and wherein the railway component is molded or formedfrom a thermoplastic polymer composition comprising 50 to 93 wt. %6 of apolycarbonate copolymer comprising bisphenol A carbonate units and unitsof the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to fiveC₁₋₁₀ alkyl groups, or C₁₋₄ alkyl (specifically unsubstituted phenyl); 4to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol Acarbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing (specificallyof formula 9b-2), wherein E has an average value of 2 to 200(specifically 12 to 100, 2 to 60, or 3 to 30), wherein thepoly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane unitsbased on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. %of an organophosphorus compound in an amount effective to provide 0.1 to2.0 wt. % of phosphorus, based on the total weight of the thermoplasticpolymer composition; and optionally, up to 5 wt. % of an additiveselected from a processing aid, a heat stabilizer, an ultra violet lightabsorber, a colorant, or a combination comprising at least one of theforegoing, wherein an article having a thickness of 0.5 to 10 mm moldedfrom the composition has a Ds-4 smoke density of less than or equal to300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m²,and a MAHRE of less than or equal to 90 kW/m² measured according to ISO5660-1 on a 3 mm thick plaque at 50 kW/m², a multiaxial impact energy ator above 100 J and a ductility of 80 to 100%, measured at +23° C. at animpact speed of 4.4 m/second according to ISO 6603 on 3.2 mm thickdiscs, and optionally, a melt volume flow rate of greater than 4 cc/10min measured at 300° C. under 1.2 kg force measured according to ISO1133. Optionally, the seat component is injection molded, and thethermoplastic composition has a melt volume flow rate of equal to orgreater than 4 cc/10 min measured at 300° C. under 1.2 kg force measuredaccording to ISO 1133; or the seat component is extruded, and thethermoplastic composition has a Vicat B120 of less than 160° C. measuredaccording to ISO 306.

In a specific embodiment, the composition comprises 4 to 20 wt. % of thepoly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and amolded or formed sample of the thermoplastic polymer composition has atransmission of greater than 80% or a haze of 5 or less measuredaccording to ASTM D1003 using the color space CIE1931 (Illuminant C anda 2° observer) at a thickness of 3 mm. These transparencies can beachieved by use of a PC-siloxane comprising carbonate units (1) derivedfrom bisphenol A, and repeating siloxane units (9b-2). (9b-3), (9b-4),or a combination comprising at least one of the foregoing (specificallyof formula 9b-2), wherein E has an average value of 4 to 50, 4 to 15,specifically 5 to 15, more specifically 6 to 15, and still morespecifically 7 to 10. The transparent PC-siloxanes can be manufacturedusing one or both of the tube reactor processes described in U.S. PatentApplication No. 2004/0039145A1 or the process described in U.S. Pat. No.6,723,864 may be used to synthesize the poly(siloxane-carbonate)copolymers.

In other specific embodiments of the foregoing seat components, one ormore of the following conditions can apply: the thermoplasticcomposition can further comprise 5 to 20 wt. % of a bisphenol Apolycarbonate; the organophosphorus compound can be an aromaticorganophosphorus compound can have at least one organic aromatic groupand at least one phosphorus-containing group, such as bisphenol Abis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenylphosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or acombination comprising at least one of the foregoing, or an organiccompound having at least one phosphorus-nitrogen bond such as aphosphazene, phosphorus ester amide, phosphoric acid amide, phosphonicacid amide, phosphinic acid amide, tris(aziridinyl) phosphine oxide, ora combination comprising at least one of the foregoing; optionally, thecomposition comprises 0.05 to 10.0 wt. % of a light diffuser additivecomprising silicone, polymethylsilsesquioxane, crosslinked poly(methylmethacrylate), methyl methacrylate/ethyleneglycol dimethacrylatecopolymer, TiO₂, or a combination comprising at least one of theforegoing, based on the total weight of the polymers in thethermoplastic composition, or 0.00002 to 5.0 wt. % of one or morecolorants based on the total weight of the polymers in the thermoplasticcomposition; or no or substantially no flame retarding brominatedcompounds, flame retardant salts, or a combination comprising at leastone of the foregoing are present in the thermoplastic composition.

Also provided herein is a railway component wherein the component is acladding, in particular an interior vertical surface, such as sidewalls, front walls, end-walls, partitions, room dividers, flaps, boxes,hoods and louvres; an interior door or lining for internal and externaldoors; a window insulation, a kitchen interior surface, an interiorhorizontal surface, such as ceiling paneling, flaps, boxes, hoods andlouvres; a luggage storage area, such as overhead and vertical luggageracks, luggage containers and compartments; a driver's desk application,such as paneling and surfaces of driver's desk; an interior surface ofgangways, such as interior sides of gangway membranes (bellows) andinterior linings; a window frame (including sealants and gaskets); a(folding) table with downward facing surface; an interior or exteriorsurface of air ducts, or a device for passenger information, such asinformation display screens, and wherein the railway component is moldedor formed from a thermoplastic polymer composition comprising, based onthe total weight of the composition. 50 to 93 wt. % of a poly(bisphenolA carbonate)-co-(bisphenol phthalate ester) (for example, comprising 75to 85 wt. % of the ester units, wherein the ester units have a molarratio of isophthalate to terephthalate of 98:2 to 88:12, or comprises 35to 45 wt. % of carbonate units and 55 to 65 wt. % of ester units,wherein the ester units have a molar ratio of isophthalate toterephthalate of 45:55 to 55:45); 4 to 30 wt. % of apoly(carbonate-siloxane) comprising bisphenol A carbonate units, andsiloxane units of the formula

or a combination comprising at least one of the foregoing (specificallyof formula 9b-2), wherein E has an average value of 2 to 200(specifically, 2 to 100, 2 to 60, or 2 to 30), wherein thepoly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane unitsbased on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. %of an organophosphorus compound in an amount effective to provide 0.1 to2.0 wt. % of phosphorus, based on the total weight of the thermoplasticpolymer composition; and optionally, up to 5 wt. % of an additiveselected from a processing aid, a heat stabilizer, an ultra violet lightabsorber, a colorant, or a combination comprising at least one of theforegoing, wherein an article having a thickness of 0.5 to 10 mm moldedfrom the composition has a Ds-4 smoke density of less than or equal to300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m²,and a MAHRE of less than or equal to 90 kW/m² measured according to ISO5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux atextinguishment (CFE) of equal to or more than 20 kW/m² measuredaccording to ISO 5658-2 at a 3 mm thick plaque, a multiaxial impactenergy at or above 100 J and a ductility of 80 to 100%, measured at +23°C. at an impact speed of 4.4 m/second according to ISO 6603 on 3.2 mmthick discs, and optionally, a melt volume flow rate of greater than 4cc/10 min measured at 300° C. under 1.2 kg force measured according toISO 1133. Optionally, the cladding is injection molded, and thethermoplastic composition has a melt volume flow rate of equal to orgreater than 4 cc/10 min measured at 300° C. under 1.2 kg force measuredaccording to ISO 1133; or the cladding is extruded, and thethermoplastic composition has a Vicat B120 of less than 160° C. measuredaccording to ISO 306.

In a specific embodiment, the composition comprises 4 to 20 wt. %/o ofthe poly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, anda molded or formed sample of the thermoplastic polymer composition has atransmission of greater than 80% or a haze of 5 or less measuredaccording to ASTM D1003 using the color space CIE1931 (Illuminant C anda 2° observer) at a thickness of 3 mm. These transparencies can beachieved by use of a PC-siloxane comprising carbonate units (1) derivedfrom bisphenol A, and repeating siloxane units (9b-2), (9b-3), (9b-4),or a combination comprising at least one of the foregoing (specificallyof formula 9b-2), wherein E has an average value of 4 to 50, 4 to 15,specifically 5 to 15, more specifically 6 to 15, and still morespecifically 7 to 10. The transparent PC-siloxanes can be manufacturedusing one or both of the tube reactor processes described in U.S. PatentApplication No. 2004/0039145A1 or the process described in U.S. Pat. No.6,723,864 may be used to synthesize the poly(siloxane-carbonate)copolymers.

In other specific embodiments of the foregoing claddings, one or more ofthe following conditions can apply; the thermoplastic composition canfurther comprise 5 to 20 wt. % of a bisphenol A polycarbonate; theorganophosphorus compound can be an aromatic organophosphorus compoundcan have at least one organic aromatic group and at least onephosphorus-containing group, such as bisphenol A bis(diphenylphosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate),tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combinationcomprising at least one of the foregoing, or an organic compound havingat least one phosphorus-nitrogen bond such as a phosphazene, phosphorusester amide, phosphoric acid amide, phosphonic acid amide, phosphinicacid amide, tris(aziridinyl) phosphine oxide, or a combinationcomprising at least one of the foregoing; optionally, the compositioncomprises 0.05 to 10.0 wt. % of a light diffuser additive comprisingsilicone, polymethylsilsesquioxane, crosslinked poly(methylmethacrylate), methyl methacrylate/ethyleneglycol dimethacrylatecopolymer, TiO₂, or a combination comprising at least one of theforegoing, based on the total weight of the polymers in thethermoplastic composition, or 0.00002 to 5.0 wt. % of one or morecolorants based on the total weight of the polymers in the thermoplasticcomposition; or no or substantially no flame retarding brominatedcompounds, flame retardant salts, or a combination comprising at leastone of the foregoing are present in the thermoplastic composition.

Specifically, the cladding can be a side wall, a front wall, anend-wall, a partition, a room divider, an interior door, a windowinsulation, a lining, a kitchen interior surface, a ceiling panel, anoverhead or vertical luggage rack, a luggage container, a luggagecompartment, a window frame, an optionally folding table with downwardfacing surface, or an information display screen. The cladding can alsobe a partition, a room divider, an interior door or lining for internaland external doors, a window insulation, an overhead and verticalluggage rack, a luggage container and compartment, a window frame; anoptionally folding table with downward facing surface; or a device forpassenger information wherein the cladding has a transmission of greaterthan 80% or a haze of 5 or less measured according to ASTM D 1003 usingthe color space CIE1931 (Illuminant C and a 2° observer) at a thicknessof 3 mm. In another embodiment, the cladding is a partition, a roomdivider, an interior door or lining for internal and external doors, awindow insulation, an overhead and vertical luggage rack, a luggagecontainer and compartment, a window frame, an optionally folding tablewith downward facing surface, or a device for passenger information,wherein the composition comprises a light diffuser additive comprising asilicone, polymethylsilsesquioxane, crosslinked poly(methylmethacrylate), methyl methacrylate/ethyleneglycol dimethacrylatecopolymer, TiO₂, or a combination comprising at least one of theforegoing.

Also provided herein is a railway component wherein the component is aninterior vertical surface, such as side walls, front walls, end-walls,partitions, room dividers, flaps, boxes, hoods and louvres; an interiordoor or lining for internal and external doors; a window insulation, akitchen interior surface, an interior horizontal surface, such asceiling paneling, flaps, boxes, hoods and louvres; a luggage storagearea, such as overhead and vertical luggage racks, luggage containersand compartments; a driver's desk application, such as paneling andsurfaces of driver's desk; an interior surface of gangways, such asinterior sides of gangway membranes (bellows) and interior linings; awindow frame (including sealants and gaskets); a (folding) table withdownward facing surface; an interior or exterior surface of air ducts,or a device for passenger information, such as information displayscreens, and wherein the railway component is molded or formed from athermoplastic polymer composition comprising, based on the total weightof the composition. 50 to 93 wt. % of a polycarbonate copolymercomprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to fiveC₁₋₁₀ alkyl groups, or C₁₋₄ alkyl (specifically unsubstituted phenyl); 4to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol Acarbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing (specificallyof formula 9b-2), wherein E has an average value of 2 to 200(specifically 2 to 100, 2 to 60 or 2 to 30), wherein thepoly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane unitsbased on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. %of an organophosphorus compound in an amount effective to provide 0.1 to2.0 wt. % of phosphorus, based on the total weight of the thermoplasticpolymer composition; and optionally, up to 5 wt. % of an additiveselected from a processing aid, a heat stabilizer, an ultra violet lightabsorber, a colorant, or a combination comprising at least one of theforegoing; wherein an article having a thickness of 0.5 to 10 mm moldedfrom the composition has a Ds-4 smoke density of less than or equal to300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m²,and a MAHRE of less than or equal to 90 kW/m² measured according to ISO5660-1 on a 3 mm thick plaque at 50 kW/m², a critical heat flux atextinguishment (CFE) of equal to or more than 20 kW/m² measuredaccording to ISO 5658-2 at a 3 mm thick plaque, a multiaxial impactenergy at or above 100 J and a ductility of 80 to 100%, measured at +23°C. at an impact speed of 4.4 m/second according to ISO 6603 on 3.2 mmthick discs, optionally, a melt volume flow rate of greater than 4 cc/10min measured at 300° C. under 1.2 kg force measured according to ISO1133. Optionally, the cladding is injection molded, and thethermoplastic composition has a melt volume flow rate of equal to orgreater than 4 cc/10 min measured at 300° C. under 1.2 kg force measuredaccording to ISO 1133; or the cladding is extruded, and thethermoplastic composition has a Vicat B120 of less than 160° C. measuredaccording to ISO 306.

In a specific embodiment, the composition comprises 4 to 20 wt. % of thepoly(carbonate-siloxane) having 1 to 10 mol % of siloxane units, and amolded or formed sample of the thermoplastic polymer composition has atransmission of greater than 80% or a haze of 5 or less measuredaccording to ASTM D1003 using the color space CIE1931 (Illuminant C anda 2° observer) at a thickness of 3 mm. These transparencies can beachieved by use of a PC-siloxane comprising carbonate units (1) derivedfrom bisphenol A, and repeating siloxane units (9b-2). (9b-3), (9b-4),or a combination comprising at least one of the foregoing (specificallyof formula 9b-2), wherein E has an average value of 4 to 50, 4 to 15,specifically 5 to 15, more specifically 6 to 15, and still morespecifically 7 to 10. The transparent PC-siloxanes can be manufacturedusing one or both of the tube reactor processes described in U.S. PatentApplication No. 2004/0039145A1 or the process described in U.S. Pat. No.6,723,864 may be used to synthesize the poly(siloxane-carbonate)copolymers.

In other specific embodiments of the foregoing claddings, one or more ofthe following conditions can apply; the thermoplastic composition canfurther comprise 5 to 20 wt. % of a bisphenol A polycarbonate; theorganophosphorus compound can be an aromatic organophosphorus compoundcan have at least one organic aromatic group and at least onephosphorus-containing group, such as bisphenol A bis(diphenylphosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate),tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combinationcomprising at least one of the foregoing, or an organic compound havingat least one phosphorus-nitrogen bond such as a phosphazene, phosphorusester amide, phosphoric acid amide, phosphonic acid amide, phosphinicacid amide, tris(aziridinyl) phosphine oxide, or a combinationcomprising at least one of the foregoing; optionally, the compositioncomprises 0.05 to 10.0 wt. % of a light diffuser additive comprisingsilicone, polymethylsilsesquioxane, crosslinked poly(methylmethacrylate), methyl methacrylatelethyleneglycol dimethacrylatecopolymer. TiO₂, or a combination comprising at least one of theforegoing, based on the total weight of the polymers in thethermoplastic composition, or 0.00002 to 5.0 wt. % of one or morecolorants based on the total weight of the polymers in the thermoplasticcomposition; or no or substantially no flame retarding brominatedcompounds, flame retardant salts, or a combination comprising at leastone of the foregoing are present in the thermoplastic composition.

Specifically, the cladding can be a side wall, a front wall, anend-wall, a partition, a room divider, an interior door, a windowinsulation, a lining, a kitchen interior surface, a ceiling panel, anoverhead or vertical luggage rack, a luggage container, a luggagecompartment, a window frame, an optionally folding table with downwardfacing surface, or an information display screen. The cladding can alsobe a partition, a room divider, an interior door or lining for internaland external doors, a window insulation, an overhead and verticalluggage rack, a luggage container and compartment, a window frame; anoptionally folding table with downward facing surface; or a device forpassenger information wherein the cladding has a transmission of greaterthan 80% or a haze of 5 or less measured according to ASTM D1003 usingthe color space CIE1931 (Illuminant C and a 2° observer) at a thicknessof 3 mm. In another embodiment, the cladding is a partition, a roomdivider, an interior door or lining for internal and external doors, awindow insulation, an overhead and vertical luggage rack, a luggagecontainer and compartment, a window frame, an optionally folding tablewith downward facing surface, or a device for passenger information,wherein the composition comprises a light diffuser additive comprising asilicone, polymethylsilsesquioxane, crosslinked poly(methylmethacrylate), methyl methacrylate/ethyleneglycol dimethacrylatecopolymer, TiO₂, or a combination comprising at least one of theforegoing

In any of the foregoing embodiments of the seat components or claddings,a sample molded from these compositions can have a smoke density after 4minutes (DS-4) of less than 300, less than 250, or less than 200measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m². Asample molded from these compositions can also have a heat release(MAHRE) of less than 90 kW/m², less than 80 kW/m², less than 70 kW/m²measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m².Furthermore, the polycarbonate compositions can have a melt volume flowrate (MVR, cubic centimeter per 10 minutes (cc/10 min) of 4 to about 15,measured at 300° C./1.2 Kg at 360 second dwell according to ISO 1133.The polycarbonate compositions can have an MAI equal to or higher than100 J, measured at 23° C. at an impact speed of 4.4 m/second accordingto ISO 6603 on discs with a thickness of 3.2 mm. The polycarbonatecompositions can have a ductility in multiaxial impact of 80% andhigher, for example 100%, measured at 23° C. at an impact speed of 4.4m/second according to ISO 6603 on discs with a thickness of 3.2 mm. Thepolycarbonate compositions can have a critical heat flux atextinguishment (CFE) of equal to or more than 20 kW/m² measuredaccording to ISO 5658-2 at a 3 mm thick plaque.

In some embodiments a combination of a bisphenol A polycarbonate and anarylate ester can be used in place of the poly(bisphenol Acarbonate)-co-(bisphenol phthalate ester). In these embodiments a moldedor extruded train seat component comprises a thermoplastic compositioncomprising, based on the total weight of the composition: 50 to 93 wt. %of a combination comprising i) 5 to 50 wt. %, or 35 to 45 wt. % of abisphenol A polycarbonate and (ii) 50 to 95 wt. %, specifically 55 to 65wt. % of a poly(bisphenol A arylate), specifically a poly(bisphenol Aarylate), based on the weight of the combination; and 4 to 30 wt. % of apoly(carbonate-siloxane) comprising bisphenol A carbonate units, andsiloxane units of the formula (9b-2), (9b-3), (9b-4), or a combinationcomprising at least one of the foregoing (specifically of formula 9b-2),wherein E has an average value of 2 to 200 (specifically. 2 to 100, 2 to60, or 2 to 30); and 3 to 20 wt. % of an organophosphorus compound, inan amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based onthe total weight of the thermoplastic polymer composition; andoptionally, up to 5 wt. % of an additive selected from a processing aid,a heat stabilizer, an ultra violet light absorber, a colorant, or acombination comprising at least one of the foregoing; wherein thecomponent has: a smoke density after 4 minutes (Ds-4) of equal to orless than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at50 kW/m², an integral of the smoke density as a function of time up to 4minutes (VOF4) of equal to or less than 6(X) measured according to ISO5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heatrelease (MAHRE) of equal to or less than 90 kW/m² measured according toISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility inmultiaxial impact of 80 to 100%, measured at +23° C. at an impact speedof 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.Optionally, the seat component is injection molded, and thethermoplastic composition has a melt volume flow rate of equal to orgreater than 4 cc/10 min measured at 300° C. under 1.2 kg force measuredaccording to ISO 1133, or the seat component is extruded, and formed,and the thermoplastic composition has a Vicat B120 of less than 140° C.measured according to ISO 306.

Optionally, the thermoplastic composition can comprise from 4 to 20 wt.% of the poly(carbonate-siloxane) comprising from 1 to 10 wt. %° ofsiloxane units based on the total weight of thepoly(carbonate-siloxane), wherein a molded or formed sample of thethermoplastic polymer composition has a transmission of greater than 80%or a haze of 5 or less measured according to ASTM D 1003 using the colorspace CIE1931 (Illuminant C and a 2° observer) at a thickness of 3 mm.

In other specific embodiments of the foregoing seat components, one ormore of the following conditions can apply: the thermoplasticcomposition can further comprise 5 to 20 wt. % of a bisphenol Apolycarbonate; the organophosphorus compound can be an aromaticorganophosphorus compound can have at least one organic aromatic groupand at least one phosphorus-containing group, such as bisphenol Abis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenylphosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or acombination comprising at least one of the foregoing, or an organiccompound having at least one phosphorus-nitrogen bond such as aphosphazene, phosphorus ester amide, phosphoric acid amide, phosphonicacid amide, phosphinic acid amide, tris(aziridinyl) phosphine oxide, ora combination comprising at least one of the foregoing; optionally, thecomposition comprises 0.05 to 10.0 wt. % of a light diffuser additivecomprising silicone, polymethylsilsesquioxane, crosslinked poly(methylmethacrylate), methyl methacrylate/ethyleneglycol dimethacrylatecopolymer, TiO₂, or a combination comprising at least one of theforegoing, based on the total weight of the polymers in thethermoplastic composition, or 0.00002 to 5.0 wt. % of one or morecolorants based on the total weight of the polymers in the thermoplasticcomposition; or no or substantially no flame retarding brominatedcompounds, flame retardant salts, or a combination comprising at leastone of the foregoing are present in the thermoplastic composition.

Also provided herein is a railway component wherein the component is acladding, in particular an interior vertical surface, such as sidewalls, front walls, end-walls, partitions, room dividers, flaps, boxes,hoods and louvres; an interior door or lining for internal and externaldoors; a window insulation, a kitchen interior surface, an interiorhorizontal surface, such as ceiling paneling, flaps, boxes, hoods andlouvres; a luggage storage area, such as overhead and vertical luggageracks, luggage containers and compartments, a driver's desk application,such as paneling and surfaces of driver's desk; an interior surface ofgangways, such as interior sides of gangway membranes (bellows) andinterior linings; a window frame (including sealants and gaskets); a(folding) table with downward facing surface; an interior or exteriorsurface of air ducts, or a device for passenger information, such asinformation display screens, and wherein the railway component is moldedor formed from a thermoplastic polymer composition comprising, based onthe total weight of the composition: 50 to 93 wt. % of a combinationcomprising i) 5 to 50 wt. %/o, or 35 to 45 wt. % of a bisphenol Apolycarbonate and (ii) 50 to 95 wt. %, specifically 55 to 65 wt. % of apoly(bisphenol A arylate), specifically a poly(bisphenol A arylate),based on the weight of the combination; and 4 to 30 wt. % of apoly(carbonate-siloxane) comprising bisphenol A carbonate units, andsiloxane units of the formula (9b-2), (9b-3), (9b-4), or a combinationcomprising at least one of the foregoing (specifically of formula 9b-2),wherein E has an average value of 2 to 200 (specifically, 2 to 100, 2 to60, or 2 to 30); and 3 to 20 wt. % of an organophosphorus compound, inan amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based onthe total weight of the thermoplastic polymer composition; andoptionally, up to 5 wt. % of an additive selected from a processing aid,a heat stabilizer, an ultra violet light absorber, a colorant, or acombination comprising at least one of the foregoing; wherein thecomponent has: a smoke density after 4 minutes (Ds-4) of equal to orless than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at50 kW/m², an integral of the smoke density as a function of time up to 4minutes (VOF4) of equal to or less than 600 measured according to ISO5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heatrelease (MAHRE) of equal to or less than 90 kW/m² measured according toISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility inmultiaxial impact of 80 to 100%, measured at +23° C. at an impact speedof 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.Optionally, the cladding is injection molded, and the thermoplasticcomposition has a melt volume flow rate of equal to or greater than 4cc/10 min measured at 300° C. under 1.2 kg force measured according toISO 1133, or the seat component is extruded, and formed, and thethermoplastic composition has a Vicat B120 of less than 140° C. measuredaccording to ISO 306.

Optionally, the thermoplastic composition can comprise from 4 to 20 wt %of the poly(carbonate-siloxane) comprising from 1 to 10 wt. % ofsiloxane units based on the total weight of thepoly(carbonate-siloxane), wherein a molded or formed sample of thethermoplastic polymer composition has a transmission of greater than 80%or a haze of 5 or less measured according to ASTM D1003 using the colorspace CIE1931 (Illuminant C and a 20 observer) at a thickness of 3 mm.

In other specific embodiments of the foregoing claddings, one or more ofthe following conditions can apply; the thermoplastic composition canfurther comprise 5 to 20 wt. % of a bisphenol A polycarbonate; theorganophosphorus compound can be an aromatic organophosphorus compoundcan have at least one organic aromatic group and at least onephosphorus-containing group, such as bisphenol A bis(diphenylphosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate),tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combinationcomprising at least one of the foregoing, or an organic compound havingat least one phosphorus-nitrogen bond such as a phosphazene, phosphorusester amide, phosphoric acid amide, phosphonic acid amide, phosphinicacid amide, tris(aziridinyl) phosphine oxide, or a combinationcomprising at least one of the foregoing; optionally, the compositioncomprises 0.05 to 10.0 wt. % of a light diffuser additive comprisingsilicone, polymethylsilsesquioxane, crosslinked poly(methylmethacrylate), methyl methacrylate/ethyleneglycol dimethacrylatecopolymer, TiO₂, or a combination comprising at least one of theforegoing, based on the total weight of the polymers in thethermoplastic composition, or 0.00002 to 5.0 wt. % of one or morecolorants based on the total weight of the polymers in the thermoplasticcomposition; or no or substantially no flame retarding brominatedcompounds, flame retardant salts, or a combination comprising at leastone of the foregoing are present in the thermoplastic composition.

Specifically, the cladding can be a side wall, a front wall, anend-wall, a partition, a room divider, an interior door, a windowinsulation, a lining, a kitchen interior surface, a ceiling panel, anoverhead or vertical luggage rack, a luggage container, a luggagecompartment, a window frame, an optionally folding table with downwardfacing surface, or an information display screen. The cladding can alsobe a partition, a room divider, an interior door or lining for internaland external doors, a window insulation, an overhead and verticalluggage rack, a luggage container and compartment, a window frame; anoptionally folding table with downward facing surface; or a device forpassenger information wherein the cladding has a transmission of greaterthan 80% or a haze of 5 or less measured according to ASTM D1003 usingthe color space CIE1931 (Illuminant C and a 2° observer) at a thicknessof 3 mm. In another embodiment, the cladding is a partition, a roomdivider, an interior door or lining for internal and external doors, awindow insulation, an overhead and vertical luggage rack, a luggagecontainer and compartment, a window frame, an optionally folding tablewith downward facing surface, or a device for passenger information,wherein the composition comprises a light diffuser additive comprising asilicone, polymethylsilsesquioxane, crosslinked poly(methylmethacrylate), methyl methacrylate/ethyleneglycol dimethacrylatecopolymer, TiO₂, or a combination comprising at least one of theforegoing.

In still another embodiment, a molded or extruded train seat componentcomprises a thermoplastic composition comprising, based on the totalweight of the composition: 75 to 96.5 wt. % of a poly(bisphenol Acarbonate)-co-(bisphenol phthalate ester) (for example, comprising 75 to85 wt. % of the ester units, wherein the ester units have a molar ratioof isophthalate to terephthalate of 98:2 to 88:12, or comprises 35 to 45wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein theester units have a molar ratio of isophthalate to terephthalate of 45:55to 55:45); 0.5 to 5 wt. %, specifically 0.5 to 3 wt. %, of apoly(siloxane) oil (for example a poly(dimethyl siloxane) oil); 3 to 20wt. % of an organophosphorus compound in an amount effective to provide0.1 to 2.0 wt. % of phosphorus, based on the total weight of thethermoplastic polymer composition; and optionally, up to 5 wt. % of anadditive selected from a processing aid, a heat stabilizer, an ultraviolet light absorber, a colorant, or a combination comprising at leastone of the foregoing; wherein the component has: a smoke density after 4minutes (Ds-4) of equal to or less than 300 measured according to ISO5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smokedensity as a function of time up to 4 minutes (VOF4) of equal to or lessthan 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50kW/m², a maximum average heat release (MAHRE) of equal to or less than90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at+23° C. at an impact speed of 4.4 m/second measured according to ISO6603 on 3.2 mm thick discs. Optionally, the seat component is injectionmolded, and the thermoplastic composition has a melt volume flow rate ofequal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kgforce measured according to ISO 1133, or the seat component is extruded,and formed, and the thermoplastic composition has a Vicat B120 of lessthan 140° C. measured according to ISO 306.

Alternatively, an extruded or molded interior train cladding comprises athermoplastic composition comprising, based on the total weight of thecomposition: 75 to 96.5 wt. % of a poly(bisphenol Acarbonate)-co-(bisphenol phthalate ester) (for example, comprising 75 to85 wt. % of the ester units, wherein the ester units have a molar ratioof isophthalate to terephthalate of 98:2 to 88:12, or comprises 35 to 45wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein theester units have a molar ratio of isophthalate to terephthalate of 45:55to 55:45); 0.5 to 5 wt. %, specifically 0.5 to 3 wt. %, of apoly(siloxane) oil (for example a poly(dimethyl siloxane) oil); 3 to 20wt. % of an organophosphorus compound in an amount effective to provide0.1 to 2.0 wt. % of phosphorus, based on the total weight of thethermoplastic polymer composition; and optionally, up to 5 wt. % of anadditive selected from a processing aid, a heat stabilizer, an ultraviolet light absorber, a colorant, or a combination comprising at leastone of the foregoing; wherein the component has: a smoke density after 4minutes (Ds-4) of equal to or less than 300 measured according to ISO5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smokedensity as a function of time up to 4 minutes (VOF4) of equal to or lessthan 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50kW/m², a maximum average heat release (MAHRE) of equal to or less than90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at+23° C. at an impact speed of 4.4 m/second measured according to ISO6603 on 3.2 mm thick discs. Optionally, the seat component is injectionmolded, and the thermoplastic composition has a melt volume flow rate ofequal to or greater than 4 cc/10 min measured at 300° C. under 1.2 kgforce measured according to ISO 1133, or the seat component is extruded,and formed, and the thermoplastic composition has a Vicat B120 of lessthan 140° C. measured according to ISO 306.

The seat components or cladding having low smoke density and low heatrelease rates are further illustrated by the following non-limitingexamples.

EXAMPLES

The materials used in the Examples are described in Table 2A.

TABLE 2A Component Chemical Description Source PC1 Linear Bisphenol APolycarbonate, produced SABIC via interfacial polymerization, Mw ofabout 30,000 g/mol as determined by GPC using polycarbonate standards,phenol end-capped PC2 Linear Bisphenol A Polycarbonate, produced SABICvia interfacial polymerization, Mw of about 21,800 g/mol as determinedby GPC using polycarbonate standards, phenol end-capped PC3 BranchedBisphenol A polycarbonate, produced SABIC via interfacialpolymerization, 0.3 mol % 1,1,1- tris(4-hydroxyphenyl)ethane (THPE)branching agent, Mw about 33,600 g/mol as determined by GPC usingpolycarbonate standards, para-cumylphenol (PCP) end-capped PC4 LinearBisphenol A Polycarbonate, produced SABIC via interfacialpolymerization, Mw of about 18,800 g/mol as determined by GPC usingpolycarbonate standards, para-cumylphenyl (PCP) end-capped PPP-BP/BPAPPP-BP (N-phenylphenolphthaleinylbisphenol, SABIC2,2-bis(4-hydro)-Bisphenol A Polycarbonate copolymer, produced viainterfacial polymerization, 32 mol % PPP-BP, Mw abort 25,000 g/mol asdetermined by GPC using polycarbonate standards, para-cumylphenol (PCP)end-capped SiPC1 PDMS (polydimethylsiloxane)-Bisphenol SABIC APolycarbonate copolymer, produced via interfacial polymerization, 20 wt.% siloxane containing eugenol endcaps, average PDMS block length of 45units (D45), Mw about 30,000 g/mol as determined by GPC usingpolycarbonate standards, para-cumyphenol (PCP) end-capped* SiPC2 PDMS(polydimethylsiloxane)-Bisphenol SABIC A Polycarbonate copolymer,produced via interfacial polymerization, 6 wt. % siloxane containingeugenol endcaps, average PDMS block of 45 units (D45), Mw about 23,000g/mol as determined by GPC using polycarbonate standards,para-cumylphenol (PCP) end-capped* SiPC3 PDMS(polydimethylsiloxane)-Bisphenol SABIC A Polycarbonate copolymer,produced via interfacial polymerization, 1 wt. % siloxane containingeugenol endcaps, average PDMS block length of 10 units (D10), Mw about22,500 g/mol as determined by GPC using polycarbonate standards,para-cumylphenol (PCP) end-capped SiPC4 PDMS(polydimethylsiloxane)-Bisphenol A SABIC Polycarbonatecoplymer,nproduced via interfacial polymerization, 20 wt. % siloxanecontaining eugenol endcap, average PDMS block length of 90 units (D90),Mw about 30.000 g/mol as determined by GPC using Polycarbonatestandards, para-cumylphenol (PCP) end-capped PC-Ester1Poly(phthalate-carbonate) copolymer, SABIC produced via interfacialpolymerization, about 81 mol % ester units, Mw about 28,500 g/mol asdetermined via GPC using polycarbonate standards, para-cumylphenol (PCP)end-capped PC-Ester2 Poly(phthalate-carbonate) copolymer, SABIC producedvia interfacial polymerization, about 60 mol % ester units, Mw about35,400 g/mol as determined via GPC using polycarbonate standards,para-cumylphenol (PCP) end-capped PDMS 100 Polydimethylsiloxane (PDMS)oil, M100 (100 cps) MOMENTIVE PDMS 350 Polydimethylsiloxane (PDMS) oil,M350 (350 cps) MOMENTIVE PDMS 1000 Polydimethylsiloxane (PDMS) oil,M1000 (1000 cps) MOMENTIVE PMPS Polyphenylmethylsiloxane oil, PN200MOMENTIVE OPCTS Octaphenylcyclotetrasiloxane MOMENTIVE PEIPolyetherimide resin, made via reaction of SABIC bisphenol A dianhydridewith equimolar amount of m-phenylene diamine, Mw about 33,000 g/mol,determined via GPC using Polystyrene standards PPSU Radel 5100;poly(phenylenesulfone) SOLVAY BPADP Bisphenol A diphosphate Nagase(Europe) GmbH TiO₂ Coated titanium dioxide DuPont Titanium Carbon blackAmorphous Carbon Cabot GAFOS 168 Tris(di-butylphenyl)phosphite BASFIRGANOX 1076 Octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionateBASF PC105BR TetrabromoBPA/bisphenol A polycarbonate SABIC copolymer,bromine content of 26 wt. %, Mw about 23,700 g/mol, para-cumyl phenolend-capped KSS Potassium 3-(phenylsulfonyl)benzenesulfonate SlossIndustries Corporation Rimar Potassium nonafluoro-1-butanesulfonateLanxess Germany PTFE Encapsulated PTFE SABIC ABS R360Acrylonitrile-butadiene-styrene resin, SABIC 360, butadiene content51.8%, styrene content 36.9%, acrylonitrile content 11.3% *Can bemanufactured by the methods described in U.S. Pat. No. 6,072,011 toHoover.

The tests performed are summarized in Table 2B.

TABLE 2B Description Test Conditions Specimen Property Units ISO SmokeISO 5659-2 50 kW/m² plaque 75 × DS-4 [—] density 75 × 3 mm ISO Heat ISO5660-1 50 kW/m² plaque 100 × MAHRE kW/m² release 100 × 3 mm ISO FlameISO 5658-2 plaque 800 × CFE kW/m² spread 155 × 3 mm Melt volume ISO 1133300° C., 1.2 Pellets MVR cm³/10 min rate kg, dwell time 300 s Meltviscosity ISO 1143 300° C., shear Pellets MV Pa · s rate of 1500 s⁻¹Multiaxial Impact, ISO 6603 4.4 m/s, Disc, 3.2 mm MAI J (Energy), %Energy and temperatures thickness, (Ductility) Ductility of 23° C. and100 mm 0° C. diameter Vicat, B120 ISO 306 B120 Multi-purpose Vicat ° C.ISO 3167 Type A, 4 mm thickness Trans- ASTM D1003 plaque 75 × Trans- %mission 75 × 3 mm mission Maze ASTM D1003 plaque 75 × Haze — 75 × 3 mm

Blending, Extrusion, and Molding Conditions

The compositions were made as follows. All solid additives (e.g.,stabilizers, colorants, solid flame retardants) were dry blendedoff-line as concentrates using one of the primary polymer powders as acarrier and starve-fed via gravimetric feeder(s) into the feed throat ofthe extruder. The remaining polymer(s) were starve-fed via gravimetricfeeder(s) into the feed throat of the extruder as well. The liquid flameretardants (e.g., BPADP) were fed before the vacuum using a liquidinjection system. It will be recognized by one skilled in the art thatthe method is not limited to these temperatures or processing equipment.

Extrusion of all materials was performed on a 25 mm Wemer-Pfleiderer ZAKtwin-screw extruder (L/D ratio of 33/1) with a vacuum port located nearthe die face. The extruder has 9 zones, which were set at temperaturesof 40° C. (feed zone). 200° C. (zone 1), 250° C. (zone 2), 270° C. (zone3) and 280-300° C. (zone 4 to 8). Screw speed was 300 rpm and throughputwas between 15 and 25 kg/hr. It will be recognized by one skilled in theart that the method is not limited to these temperatures or processingequipment.

The compositions were molded after drying at 100-110° C. for 6 hours ona 45-ton Engel molding machine with 22 mm screw or 75-ton Engel moldingmachine with 30 mm screw operating at a temperature 270-300° C. with amold temperature of 70-90° C. It will be recognized by one skilled inthe art that the method is not limited to these temperatures orprocessing equipment.

ISO smoke density measurements were performed on 7.5×7.5 cm plaques with3 mm thickness using an NBS Smoke Density Chamber from Fire TestingTechnology Ltd (West Sussex, United Kingdom). All measurements wereperformed according to ISO 5659-2, with an irradiance of 50 kW/m² at thesample position and a sample-to-cone distance of 5 cm in view of thecharring behavior of the samples (as prescribed by ISO 5659-2). DS-4 wasdetermined as the measured smoke density after 240 seconds. The testsexecuted are indicative tests. They were performed according to theISO5659-2 standard, but were not executed by an officially certifiedtest institute.

ISO heat release measurements were performed on 10×10 cm plaques with 3mm thickness using a Cone Calorimeter. All measurements were performedaccording to ISO 5660-1, with 50 kW/m² irradiance at the sample positionand a sample-to-cone distance of 6 cm in view of the charring behaviorof the samples (as prescribed by ISO 5660-1). Heat release is measuredas MAHRE in kW/m² as prescribed by ISO5660-1. The tests executed areindicative tests, and were executed by an officially certified testinstitute.

ISO flame spread measurements were performed on an 800×155 mm plaqueswith 3 mm thickness using according to ISO 5658-2. Flame spread ismeasured as critical heat flux at extinguishment (CFE) in kW/m² asprescribed by ISO 5658-2. The tests executed are official tests executedby an officially certified test institute according to ISO 5658-2.Silicon content is a weight percent calculated by dividing the totalweight of silicon atoms in a composition over the total weight of thecomposition.

Examples 1-13

Examples 1-13 demonstrate the effect of the addition of variouspolycarbonate-siloxane copolymers and polydimethylsiloxane (PDMS) oil toPPP-BP/BPA copolymers on smoke density, transparency, and hazeproperties. Formulations and results are shown in Table 3. The resultsare also illustrated graphically in FIGS. 1 and 2. Comparative Examples1 and 6 show that both PPP-BP/BPA copolymer andpolydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. %siloxane units (SiPC2) have relatively high smoke densities (DS-4) at 50kW/m², measured according to ISO5659-2, far exceeding Hazard Level 2requirements for EN45545 R1 or R6 applications (DS-4<300 at 50 kW/m).Surprisingly, when relatively low amounts of SiPC2 are added toPPP-BP/BPA copolymer, the DS-4 values of the composition containing bothSiPC2 and PPP-BP/BPA decrease significantly (Examples 2-4) as comparedto compositions containing SiPC2 but not PPP-BP/BPA (Comparative Example6) and compositions containing PPP-BP/BPA but not SiPC2 (ComparativeExample 1).

Furthermore, there is an optimum in the amount of SiPC2 that may beadded, on the smoke density improvement. FIG. 1 shows that forconcentrations of SiPC2 above 10 wt. %, the smoke density values startto increase again. For the optimum SiPC2 loadings, the smoke density isreduced to such an extent that obtained DS-4 values for compositionscontaining SiPC2 and PPP-BP/BPA are below the HL2 thresholds for EN45545R1 or R6 HL-2 qualifying applications (DS-4<300 at 50 kW/m²). Too highSiPC2 loadings (>20 wt. %) result in a higher DS-4 value far exceedingthe DS-4 threshold of 300 at 50 kW/m² for HL2 compliant R1 or R6applications.

The improvement in smoke density is also observed when otherpolydimethylsiloxane/bisphenol A polycarbonate copolymer types are addedto the PPP-BP/BPA copolymer, as can be seen for bothpolydimethylsiloxane/bisphenol A polycarbonate copolymer having 20 wt. %siloxane units, (SiPC1, examples 7-9) and polydimethylsiloxane/bisphenolA polycarbonate copolymer having 1 wt. % siloxane units (SiPC3, Examples10 and 11). There are some differences in the ability of differentpolydimethylsiloxane/bisphenol A polycarbonate copolymer types to reducesmoke density of PPP-BP/BPA copolymer even at similar silicon contents.Nonetheless, the addition of optimal amounts of SiPC1. SiPC2 and SiPC3to PPP-BP/BPA copolymer reduces the smoke density to such an extent thatobtained DS-4 values for compositions containing PPP-BP/BPA and SiPC areclose to or below the thresholds HL-2 applications (DS-4<300 at 50kW/m²).

Using relatively small amounts of either polydimethylsiloxane-bisphenolA polycarbonate copolymer having 6 wt. %/siloxane units (SiPC2, 10 wt. %max) or polydimethylsiloxane/bisphenol A polycarbonate copolymer having1 wt. % siloxane units (SiPC3) retains the relatively high transmissionvalues of PPP-BP/BPA copolymer of 80% and higher and keeps the hazeincrease to acceptable levels below 5. The addition of thepolydimethylsiloxane/bisphenol A polycarbonate copolymer having 20 wt. %siloxane units, on the other hand, results in significant reduction intransmission and increase in haze because of the opaque nature of thisSiPC type. As such, addition of SiPCl to PPP-BP/BPA copolymer to reducesmoke density in rail components to meet EN45545 R3, R1 or R6 qualifyingapplication is only suitable when targeting non-transparentapplications. The same is true for SiPC2, if the loadings are above 10wt. %. In general, transparent compositions can be tuned by the amountof polydimethylsiloxanebisphenol A polycarbonate copolymer and itsarchitecture.

From Comparative Examples 12 and 13, it is evident thatpolydimethylsiloxane (PDMS) oil results only in minor reductions insmoke density of PPP-BP/BPA, much less than observed for any of thepolydimethylsiloxane/bisphenol A polycarbonate copolymers at similarsilicon content. Furthermore, the PPP-BP/BPA samples turn completelyopaque after PDMS oil is added, since PDMS is not miscible with thePPP-BP/BPA copolymer. As such, polydimethylsiloxane/bisphenol Apolycarbonate copolymers are much more suitable for reducing the smokedensity of PPP-BP/BPA copolymers than PDMS oil, despite the similarnature of the siloxane (polydimethylsiloxane).

Examples 30-53

Examples 30-53 demonstrate the effect of the addition of variouspolydimethylsiloxane/bisphenol A polycarbonate copolymers andpolysiloxanes to poly(phthalate-carbonate) copolymer (PC-Ester1) onsmoke density, transmission, and haze.

Examples 30-37

These examples show the effect of adding polydimethylsiloxane/bisphenolA polycarbonate copolymer having 6 wt. % siloxane units (SiPC2) topoly(phthalate-carbonate) copolymer having 81 mol % ester units(PC-Ester1). Formulations and results are shown in Table 6. The resultsare illustrated graphically in FIG. 3.

TABLE 6 Unit CEx30 Ex31 Ex32 Ex33 Ex34 Ex35 CEx36 CEx37 ComponentPC-Ester 1 Wt. % 100.00 94.95 89.95 82.45 74.95 67.45 59.95 SiPC2 Wt. %5.00 10.00 17.50 25.00 32.50 40.00 100 Irgafos 168 Wt. % 0.05 0.05 0.050.05 0.05 0.05 Si content Wt. % 0.00 0.10 0.21 0.36 0.52 0.68 0.83 2.08Property Smoke density, DS-4 — 1140 269 308 286 219 389 983 930Transmission % 87.7 86.3 79.9 61.8 50.9 42.5 38.1 87.6 Haze — 1.42 2.126.56 28.8 49 67.4 77.9 2.48

Comparative Examples 30 and 37 show that both poly(phthalate-carbonate)copolymer having 81 mol % ester units (PC-Ester1) andpolydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. %6siloxane units (SiPC2) have a smoke density value (DS-4) that is high(1140 and 930 at 50 kW/m², respectively for comparative examples 30 and37), to the point where compositions made from PC-Ester1 alone or SiPC2alone would not comply with the EN45545 rail standard (2013) thresholdfor qualifying under R1 or R6 material selection criteria for any HazardLevel (HL) applications (DS-4<600 for HL-1, DS-4<300 for HL2 andDS-4<150 for HL3, all at 50 kW/m²).

Again, adding small amounts of SiPC2 to PC-Ester1 decreases the smokedensity values significantly (Examples 31-35). The decrease in smokedensity is dependent on the SiPC2 content, with DS-4 values below 300 at50 kW/m² for SiPC2 loadings between 5 and 25% (Examples 31-35). Asillustrated graphically in FIG. 3, too high SiPC2 loadings result in atoo high DS-4 value (983 at 50 kW/m²) again (Comparative Example 36),similar to the DS-4 value of pure SiPC2 (930 at 50 kW/m², ComparativeExample 37). The addition of optimal amounts of SiPC2 to PC-Ester1reduces the smoke density to such an extent that obtained DS-4 valuesfor compositions containing PC-Ester1 and SiPC2 are close to or belowthe thresholds for EN45545 R1 or R6 HL-2 applications (DS-4<300 at 50kW/m²).

The addition of SiPC2 to PC-Ester1 reduces the transmission andincreases the haze with increasing SiPC2 contents. At low SiPC2contents, the reduction in transmission is relatively limited withtransmission values of 80% and higher and haze values of 10 and lower.By optimizing the polydimethylsiloxane/bisphenol A polycarbonatecopolymer content and its architecture, a combination of both low smokedensity and acceptable optical properties can be achieved.

Examples 38-44 and 47-53

These examples demonstrate the effect of adding differentpolydimethylsiloxane/bisphenol A polycarbonate copolymer andpolysiloxanes to poly(phthalate-carbonate) copolymer having 81 mol %ester units (PC-Ester 1) on smoke density. Formulations and results areshown in Table 7. The results are also graphically illustrated in FIGs 6and 7.

Examples 37-44 demonstrate the effect of adding differentpolydimethylsiloxane/bisphenol A polycarbonate copolymers havingdifferent mol percentages of siloxane units (SiPC1, 2, 3, and 4) topoly(phthalate-carbonate) copolymer

TABLE 3 Unit CEx 1 Ex 2 Ex 3 Ex 4 CEx 5 CEx 6 CEx 7 Ex 8 Ex 9 Ex 10 CEx11 CEx 12 CEx 13 Component PPP-BP/BPA Wt. % 100.00 89.95 79.95 69.9559.95 96.95 93.95 89.95 83.45 66.65 99.4 98.57 SiPC2 Wt. % 10.00 20.0030.00 40.00 100.00 SiPC1 Wt. % 3.00 6.00 10.00 SiPC3 Wt. % 16.50 33.30PDMS 1000 Wt. % 0.55 1.38 Irgafos 168 Wt. % 0.05 0.05 0.05 0.05 0.050.05 0.05 0.05 0.05 0.05 0.05 Si content Wt. % 0.00 0.21 0.42 0.62 0.832.08 0.21 0.42 0.69 0.06 0.13 0.21 0.52 Property Smoke density, — 626237 323 415 421 935 545 341 218 366 567 587 569 DS-4 Transparency % 88.481.9 67.7 53.6 6 87.6 36.2 28.3 21.4 88.4 88.6 30.6 24.7 Haze — 1.14 3.818.1 42.8 19.0 2.48 104 104 104 0.78 0.89 104 104

TABLE 7 Unit Ex 38 Ex 39 Ex 40 Ex 41 Ex 42 Ex 43 Ex 44 ComponentPC-Ester 1 Wt. % 96.88 92.38 87.88 74.88 49.88 96.88 92.38 SiPC1 Wt. %3.00 7.50 12.00 SiPC3 Wt. % 25.00 50.00 SiPC4 Wt. % 3.00 7.50 PDMS 1000Wt. % PMPS Wt. % OPCTS Wt. % Irgafos 168 Wt. % 0.08 0.08 0.08 0.08 0.080.08 0.08 Antioxidant 1076 Wt. % 0.04 0.04 0.04 0.04 0.04 0.04 0.04 Sicontent Wt. % 0.21 0.52 0.83 0.09 0.19 0.21 0.53 Property Smoke density,DS-4 — 388 263 280 592 354 346 239 Transmission % 39.7 27.7 20.1 89.789.4 36.7 24.2 Haze — 97.4 104 104 0.55 0.64 104 104 CEx 47 Ex 48 Ex 49CEx 50 CEx 51 CEx 52 CEx 53 Component PC-Ester 1 99.33 98.50 97.68 98.8597.36 98.39 96.19 SiPC1 SiPC3 SiPC4 PDMS 1000 0.55 1.38 2.20 PMPS 1.032.52 OPCTS 1.49 3.69 Irgafos 168 0.08 0.08 0.08 0.08 0.08 0.08 0.08Antioxidant 1076 0.04 0.04 0.04 0.04 0.04 0.04 0.04 Si content 0.21 0.520.83 0.21 0.52 0.21 0.52 Property Smoke density, DS-4 510 217 279 778553 560 592 Transmission 29.4 18.7 16.4 90.0 89.7 89.1 89.7 Haze 104 104104 0.51 0.48 1.13 1.43having 81 mol % ester units (PC-Ester1) on smoke density. Table 7 andFIG. 6 show that for the different SiPC types, similar improvements inDS-4 values are achieved, independent of the SiPC architecture. Inparticular, DS-4 values are in the same range for the different SiPCtypes at the same silicon content. At a silicon content of 0.21 wt. %,DS-4 values of 300 to 400 are obtained for SiPC1 (Example 38), SiPC2(Example 32) and SiPC4 (Example 43), all measured according to IS05659-2at 3 mm thickness at 50 kW/m². At a silicon content of 0.52 wt. %, DS-4values of 200 to 280 are obtained for SiPC1 (Example 39), SiPC2 (Example34) and SiPC4 (Example 44), all measured according to IS05659-2 at 3 mmthickness at 50 kW/m².

Results show that the siloxane content in thepolydimethylsiloxane/bisphenol A polycarbonate copolymer has nosignificant influence on the smoke density when compared at the samesilicon content in the final formulation, comparing SiPC1 (20 wt. % D45)and SiPC2 (6 wt. % D45).

Similarly, the D-length of the siloxane block does not have asignificant influence on the smoke density when compared at the samesilicon content in the final formulation, comparing SiPC1 (20 wt. % D45)and SiPC4 (20 wt. % D90), as well as SiPC3 (D-length of 10 units, butalso a different content).

In all cases, DS-4 values can be achieved close to or below the HL-2thresholds for EN45545 R1 or R6 applications (DS-4<300 at 50 kW/m²),depending on the SiPC content in the composition, provided the otherrequirements (e.g. heat release) are also met.

Examples 47-53 (Table 7 and FIG. 5) show that the effects on smokedensity reduction of PC-Ester 1 are different for siloxane oils comparedto SiPC copolymers. Polydimethyl siloxane (PDMS) oil also givesimprovements in DS-4, but is less efficient. For example, higher siliconcontents are needed to achieve a DS-4 value meeting the HL-2requirements for R1 or R6 applications (DS-4<300 at 50 kW/m²).Polymethylphenylsiloxane (PMPS) oil as well asoctaphenylcyclotetrasiloxane (OPCTS) does not improve smoke density ofPC-Ester1 copolymer as efficient as PDMS oil, demonstrating the need foran aliphatic siloxane type (PDMS) instead of aromatic siloxanes. This ishighly unexpected, as for other flame properties, such as UL V-4)compliance, the siloxane of choice are typically phenyl based (likeoctaphenylcyclotetrasiloxane or polyphenylmethylsiloxane) rather thanPDMS.

PDMS oil may have the disadvantages of opaqueness and potential forbleach out, due to inherent immiscibility with polycarbonate and itscopolymers. Nevertheless, PDMS oil can be formulated to PC-Ester1 toobtain a composition that has a smoke density close to or below the HL-2threshold for EN45545 R1 or R6 applications (DS-4<300 at 50 kW/m²),provided the other requirements (e.g. heat release) are also met.

Examples 54-58

Examples 54-58 demonstrate the effect of addingpolydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 mol %siloxane units (SiPC2) to linear bisphenol A polycarbonate resin (PC1).Formulations and results are shown in Table 8.

TABLE 8 Unit CEx 54 CEx 55 CEx 56 CEx 57 CEx 58 Component PC1 Wt. %100.00 87.15 74.95 49.95 SiPC2 Wt. % 12.50 25.00 50.00 100.00 Irgafos168 Wt. % 0.05 0.05 0.05 Si content Wt. % 0 0.26 0.52 1.04 2.08 PropertySmoke density, — 979 513 569 716 935 DS-4

Comparative Examples 54 and 58 show that both linear bisphenol Apolycarbonate resin (PC1) and polydimethylsiloxane/bisphenol Apolycarbonate copolymer having 6 wt. % siloxane units (SiPC2) haverelatively high smoke densities measured according to IS05659-2 at 3 mmthickness at 50 kW/m². However, as shown in comparative Examples 55-57,when relatively low amounts of SiPC2 are added to PC1, the smoke densityvalues decrease significantly. Nonetheless, the decrease in DS-4 israther limited and the values remain rather high, and the formulationscontaining PC1 and SiPC2 do not meet the HL2 requirements for EN45545 R1or R6 applications (DS-4<300 at 50 kW/m²).

Examples 63-77

These examples demonstrate that the effect ofpolydimethylsiloxane/bisphenol A polycarbonate copolymer addition onsmoke density reduction is also applicable to compositions containingbisphenol A diphosphate (BPADP) as well.

Examples 63-72

Examples 63-72 demonstrate that the addition of BPADP together withpolydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. %siloxane units (SiPC2) to poly(phthalate-carbonate) copolymer having 81mol %6 ester units (PC-Ester1) improves the smoke density, the heatrelease and the melt flow of PC-Ester 1-containing compositions, whileretaining ductile multiaxial impact at +23° C. and 0° C. Results andformulations are shown in Table 10.

Table 10 demonstrates that BPADP has a positive effect on the smokedensity as it further reduces DS-4 values of a composition containingPC-Ester1 and SiPC2, but not BPADP, from 308 (Example 63) to valuesbetween 150 and 280 (Examples 64-72), all measured according to ISO5659-2 on 3 mm thick plaques at 50 kW/m², which is significantly belowthe 300 threshold for HL2 compliance for R1 or R6 applications, forcompositions containing PC-Ester1, SiPC2 and BPADP. The data also showsthat BPADP has a positive effect on MAHRE, as it reduces MAHRE of acomposition containing PC-Ester1 and SiPC2, but not BPADP, from 129kW/m² (Example 63) to values below the 90 kW/m² threshold (Examples64-72) for HL2 compliance for R1 or R6 applications after differentamounts of BPADP are added, all measured according to ISO5659-2 at 3 mmthickness at 50 kW/m². MAHRE values of these compositions are even closeto the 60 kW/m² threshold for HL3 compliance for R1 and R6 applications.These properties are achieved for a broad range of PC-Si2 loadings (5-30wt. % based on the total polymer content) and BPADP loadings (3.5 to 15wt. % based on the total composition). As such, the addition of BPADP tocompositions containing SiPC2 and PC-Ester1 results in compositions thatcan be fully compliant with the HL2 requirements for R1 and R6applications according to EN45545, which requires a combination of DS-4values below 300 measured according to ISO5659-2 at 3 mm thickness at 50kW/m² and MAHRE values below 90 kW/m² measured according to IS05660-1 at3 mm thickness at 50 kW/m², provided that the other required propertiesmeet the selection criteria as well. Therefore, these compositions canbe used in these types of applications.

Furthermore, BPADP also improves the melt flow, as can be seen in theincrease in MVR and decrease in MV for Examples 64-72 compared toExample 63. The MVR and MV values can be tuned by optimizing the SiPC2to PC-Ester1 ratio and/or the BPADP content of the composition. As such,MVR values between 4 and 12 cc/10 min can be achieved at 300° C. at 1.2kg, which typically allow both injection molding of parts and extrusionof sheet.

These compositions have heat properties not exceeding those of regularPC with Vicat B120 values below 140° C., as low as 113° C., which wouldallow forming of parts at conventional forming temperatures for PC.

The addition of BPADP does not significantly reduce the multiaxialimpact energy properties, since all samples retain energy levels above100 J at 23° C. and 100%

TABLE 10 Component Unit CEx 63 Ex 64 Ex 65 Ex 66 Ex 67 Ex 68 Ex 69 Ex69a PC-Ester1 Wt. % 88.07 84.92 83.12 81.31 79.63 77.94 74.57 74.54SiPC2 Wt. % 9.79 9.44 9.24 9.04 8.85 8.66 8.29 15.81 Coated TiO2 Wt. %2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 Carbon black Wt. % 0.10 0.100.10 0.10 0.10 0.10 0.10 0.10 Irgafos 168 Wt. % 0.05 0.05 0.05 0.05 0.050.05 0.05 0.05 BPADP Wt. % 0.00 3.5 5.5 7.50 9.38 11.3 15 7.50 SiPC2/PC-% 10 10 10 10 10 10 10 17.5 Ester1 ratio Smoke density, — 308 178 184194 243 205 217 157 DS-4 Heat release, kW/m² 129 NA NA 58 65 62 69 61MAHRE Vicat B120 ° C. 174 NA NA 137 132 126 114 136 MAI +23° C., J 141NA¹ NA¹ 102 NA¹ 130 121 127 Energy MAI, +23° C., % 100 NA² NA² 100 NA²100 100 100 ductility MAI, 0° C., J 130 NA¹ NA¹ 83 103 112 102 85 energyMAI, 0° C., % 100 NA² NA² 100 100 100 75 100 ductility MVR, 300° C.,Cm³/10 min 1.9 2.1 2.6 4.5 5.7 6.9 10.5 4.9 1.2 kg MV, 300° C., Pa ·s * * * 573 375 301 235 374 1500 s⁻¹ Component Ex 69b Ex 70 Ex 71 Ex 72EX 72a Ex 72b EX 72c PC-Ester1 67.76 84.10 73.00 66.40 71.45 63.60 59.85SiPC2 22.59 4.42 15.48 22.12 15.16 23.00 23.00 Coated TiO2 2.00 2.002.00 2.00 2.00 2.00 2.00 Carbon black 0.10 0.10 0.10 0.10 0.10 0.10 0.10Irgafos 168 0.05 0.05 0.05 0.05 0.05 0.05 0.05 BPADP 7.50 9.38 9.38 9.3811.25 11.25 15.00 SiPC2/PC- 25 5 17.5 25 17.5 25 28 Ester1 ratio Smokedensity, 186 206 179 177 215 184 274 DS-4 Heat release, NA 65 66 73 NA66 NA MAHRE Vicat B120 134 133 130 127 124 124 113 MAI +23° C., 113 129130 123 129 134 121 Energy MAI, +23° C., 100 100 100 100 100 100 100ductility MAI, 0° C., 96 118 104 115 119 115 126 energy MAI, 0° C., 100100 100 100 100 100 100 ductility MVR, 300° C., 5.5 5.2 6.2 7.1 7.6 7.511.2 1.2 kg MV, 300° C., 343 394 328 289 284 272 207 1500 s⁻¹ ¹It isexpected that the multiaxial impact energy will be above 100 J, as alltested compositions with higher BPADP loadings have higher energyvalues. ²It is expected that the ductility will be 100% as thecompositions with higher BPADP loadings have been tested to haveductility of 100%. * Not measurableductility, as measured according to ISO 6603 on 3.2 mm thick disks. Mostsamples retain 100% ductility even at 0° C., except the sample with thehighest BPADP loading (Example 69, 15 wt. % BPADP), which has 75%ductility. This demonstrates that ductility is retained, even atrelatively high BPADP loadings up to 11 and even 15 wt. %. As such,compositions containing SiPC2, PC-Ester1 and BPADP have a goodcombination of full HL2 compliance for R6 applications (smoke densityand heat release), sufficient melt flow for molding of large and complexparts and retention of good practical impact properties. An optimalcombination of these properties can be achieved upon proper formulation,which makes these compositions suitable for train interior parts thatfully comply with R6 HL-2 requirements. Examples 73-75

Examples 73-75 show that relatively small quantities of linear bisphenolA polycarbonate (PC4) can be added to compositions containingpolydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. %siloxane units (SiPC2) and poly(phthalate-carbonate) copolymer having 81mol % ester units (PC-Ester1), for instance to improve impact or flow,without deteriorating smoke density too much.

The formulations and the results are shown in Table 11.

TABLE 11 Unit Ex73 Ex74 Ex75 Component PC-Ester1 Wt. % 67.75 57.40 47.40SiPC2 Wt. % 22.60 23.00 23.00 PC4 Wt. % 10.00 20.00 Coated TiO₂ Wt. %2.00 2.00 2.00 Carbon black Wt. % 0.10 0.10 0.10 Irgafos 168 Wt. % 0.050.05 0.05 BPADP Wt. % 7.50 7.50 7.50 Property Smoke density, DS-4 — 186244 266 MAI +23° C., Energy J 113 123 126 MAI, +23° C., ductility % 100100 100 MAI, 0° C., energy J 96 128 136 MAI, 0° C., ductility % 100 100100 MVR, 300° C., 1.2 kg Cm³/10 min 5.5 6.6 9.6 MV, 300° C., 1500 s⁻¹ Pa· s 343 293 243

Examples 74-75 show that the addition of small quantities of linearbisphenol A polycarbonate (PC2) to a composition containing BPADP,polydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. %siloxane units (SiPC2) and poly(phthalate-carbonate) copolymer having 81mol % ester units (PC-Ester1) gives an increase in smoke density (DS-4values of 244 and 246 for Examples 74 and 75, all measured according toISO5659-2 at 3 mm thickness at 50 kW/m²) compared to the samecomposition without PC3 (DS-4 value of 186, measured according toIS05659-2 at 3 mm thickness at 50 kW/m²). However, the increase isrelatively minor and the DS-4 values still remain below the HL2threshold (DS-4<300 at 50 kW/m²) for R1 or R6 applications.

The addition of PC2 to the composition results in a significantimprovement in melt flow as evidenced by the increase in MVR (from 5.5cc/10 min for Example 73 to 6.6 cc/10 min and 9.6 cc/10 min for Examples74 and 75 respectively) and decrease in MV (from 343 Pa·s for Example 73to 293 Pa·s and 243 Pas respectively for Examples 74 and 75).

Furthermore, the addition of PC2 to the composition also results in animprovement in practical impact properties, as the multiaxial impactenergy at all measured temperatures increases for Examples 74 and 75compared to Example 73.

As such, the addition of small quantities of linear bisphenol Apolycarbonate (PC2) can be used to further improve the property profileof the compositions containing BPADP, polydimethylsiloxaneibisphenol Apolycarbonate copolymer (SiPC2) and poly(phthalate-carbonate) copolymer(PC-Ester1), including melt flow and practical impact, while retainingthe excellent smoke density properties of these compositions without thelinear bisphenol A polycarbonate.

Examples 76-77

Examples 76-77 show the effect of changing the poly(phthalate-carbonate)copolymer type (PC-Ester2 instead of PC-Ester1) in compositionscontaining polydimethylsiloxane/bisphenol A polycarbonate copolymerhaving 6 wt. % siloxane units (SiPC2), BPADP andpoly(phthalate-carbonate) copolymer.

The formulations and the results are shown in Table 12.

TABLE 12 Unit Ex76 Ex77 Component PC-Ester1 Wt. % 70.58 SiPC2 Wt. %23.53 23.53 PC-Ester2 Wt. % 70.58 Coated TiO2 Wt. % 2.00 2.00 Carbonblack Wt. % 0.10 0.10 Irgafos 168 Wt. % 0.05 0.05 BPADP Wt. % 3.75 3.75Property Smoke density, DS-4 — 194 206

Examples 76 and 77 show that comparable smoke density values areobtained when PC-Ester1 (Example 76, DS-4 of 194 at 50 kW/m²), whichcontains 81 mol % ester groups, is replaced with PC-Ester2 (Example 77,DS-4 of 206 at 50 kW/m²), which contains 60 mol % ester groups. As such,effects observed in the previous examples are not limited to PC-Ester1alone, but are also applicable to alternative types of thepoly(phthalate-carbonate) copolymer.

Example 79

Example 79 demonstrates that the addition of BPADP together withpolydimethylsiloxane/bisphenol A polycarbonate copolymer having 6 wt. %6siloxane units (SiPC2) to poly(phthalate-carbonate) copolymer having 81mol % ester units (PC-Ester1) improves the smoke density, the heatrelease, the flame spread, and the melt flow of PC-Ester 1-containingcompositions, while retaining ductile multiaxial impact at +23° C. and0° C. Results and formulations are shown in Table 13.

TABLE 13 Unit Ex79 Components, wt. % PC-Ester1 Wt. % 67.75 SiPC2 Wt. %22.60 Coated TiO2 Wt. % 2.00 Carbon black Wt. % 0.10 Irgafos 168 Wt. %0.05 BPADP Wt. % 7.50 Property Ds-4 ISO 5659-2 — 186 MAHRE ISO 5660-1kW/m² 58 CFE ISO 5658-2 kW/m² 21.2 MVR, 300° C., 1.2 kg Cc/10 min 5.5MV, 300° C., 1500 s⁻¹ Pa · s 343 MAI, +23° C., Energy J 113 MAI, +23°C., ductility % 100 MAI, 0° C. energy J 96 MAI, 0° C., ductilily % 100Vicat B120 ° C. 135

Table 13 demonstrates that compositions containing BPADP, PC-Ester1 andSiPC2 have smoke density Ds-4 values of 186 measured according toIS05659-2 at 3 mm thickness at 50 kW/m and MAHRE values of 61 kW/m²measured according to ISO5660-1 at 3 mm thickness at 50 kW/m². As such,these compositions can be fully compliant with the HL2 requirements forR6 applications according to EN45545, which requires a combination ofDS-4 values below 300 at 50 kW/m² and MAHRE values below 90 kW/m² at 50kW/m². Therefore, these compositions can be used in these types ofapplications. MAHRE values of these compositions are even close to the60 kW/m² at 50 kW/m² threshold for HL3 compliance for R1 and R6applications.

Furthermore, these combinations have an excellent combination of meltflow, as indicated by the MVR values of 5.5 cc/10 min and retainexcellent multiaxial impact properties, as indicated by the 100%ductility in multiaxial impact testing at +23° C. and 0° C. The flow canbe further tuned by optimizing the SiPC2 to PC-Ester1 ratio and/or theBPADP content of the composition. As such, compositions containingSiPC2, PC-Ester1 and BPADP have a good combination of full HL2compliance for R6 applications (smoke density and heat release),sufficient melt flow for molding of large and complex parts andretention of good practical impact properties. An optimal combination ofthese properties can be achieved upon proper formulation, which makesthese compositions suitable for train interior parts that fully complywith R6 HL-2 requirements.

The composition further has a critical heat flux at extinguishment (CFE)of 21.2 kW/m², exceeding the threshold for HL2 or HL3 requirements forR1 applications, which both require a value at or above 20 kW/m². Assuch, combined with the MAHRE and Ds-4 values described above, thesematerials are also suitable for Hazard Level 2 (HL-2) (Ds-4<300 at 50kW/m², CFE>20 kW/m² and MAHRE≦90 kW/m² at 50 kW/m²) in European Railwaystandard EN-45545 class R1 applications. This combined with the flow andimpact properties of these compositions makes these compositionsexcellent candidates for train interior parts that fully comply with R1HL-2 requirements.

Example 78

Example 78 demonstrates that, similarly to Examples 63-77, the additionof BPADP together with polydimethylsiloxane/bisphenol A polycarbonatecopolymer having 6 wt. % siloxane units (SiPC2) also improves smokedensity and heat release of PPP-BP/BPA copolymer, while maintaining goodtransmission and haze properties. Results and formulations are shown inTable 13.

TABLE 13 Unit Ex 78 Component PPP-BP/BPA Wt. % 89.68 SiPC2 Wt. % 5.00IRGANOX 1076 Wt. % 0.04 TINUVIN 329 Wt. % 0.20 Irgafos 168 Wt. % 0.08BPADP Wt. % 5.00 Property Smoke density, DS-4 — 166 Heat release, MAHREkW/m² 80 Transmission % 85.8 Haze — 1.97

Table 13 shows that the addition of both BPADP and SiPC2 to PPP-BP/BPAcopolymer results in a combination of low smoke density (DS-4 of 166measured according to IS05659-2 at 3 mm thickness at 50 kW/m²) and lowheat release (MAHRE of 80 kW/m², measured according to ISO5660-1 at 3 mmthickness at 50 kW/m²). Both values are below the HL2 thresholds for R6applications for DS-4 (<300 at 50 kW/m²) and MAHRE (<90 kW/m² at 50kW/m²), which makes these compositions fully with the HL2 requirementsfor R6 applications according to EN45545.

Furthermore, transmission is still relatively high upon addition ofsmall amounts of SiPC2 ((85.8%) and haze is still relatively low (1.97),which allows to make compositions that both are compliant with the HL2requirements for smoke density and heat release for R6 applicationsaccording to EN45545 and still have acceptable optical properties to besuitable for transparent applications, as well as diffuse, translucentand opaque colors, which can be tuned via a colorant package. Again, ingeneral, transparent compositions can be tuned by the architecture ofthe polydimethylsiloxane/bisphenol A polycarbonate copolymer.

Examples 79-86

These examples demonstrate the effect of TiO₂ addition on smoke densityreduction to compositions containing polydimethylsiloxanebisphenol Apolycarbonate copolymer having 6 wt. % siloxane units (SiPC2),poly(phthalate-carbonate) copolymer having 81 mol % ester units(PC-Ester1) and bisphenol A diphosphate (BPADP).

TABLE 14 Unit Ex 79 Ex 80 Ex 81 Ex 82 Ex 83 Ex 84 Ex 85 Ex 86 ComponentPC-Ester1 Wt. % 74.57 77.94 81.31 64.95 76.46 79.83 83.21 66.53 SiPC2Wt. % 8.29 8.66 9.04 21.65 8.50 8.87 9.25 22.18 Coated TiO2 Wt. % 2.002.00 2.00 2.00 Carbon black Wt. % 0.10 0.10 0.10 0.10 Irgafos 168 Wt. %0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 BPADP Wt. % 15 11.25 7.50 11.2515 11.25 7.50 11.25 SiPC2/PC-Ester1 % 10 10 10 25 10 10 10 25 ratioProperty Smoke density, DS-4 — 217 205 194 184 309 326 289 316

A comparison of compositions with similar BPADP loading andSiPC2/PC-Ester1 ratio with and without TiO₂ shows that TiO₂ addition hasa beneficial effect on the smoke density, comparing Examples 79 (DS-4 of217) and 83 (DS-4 of 309), Examples 80 (DS-4 of 205) and 84 (DS-4 of326). Examples 81 (DS-4 of 194) and 85 (DS-4 of 289) and Examples 82(DS-4 of 184) and 86 (316), all measured according to 1S05659-2 at 3 mmthickness at 50 kW/m². Therefore, TiO₂ can be added to the compositionto further improve the smoke density compared to the composition withoutTiO₂.

Examples 40-45

These comparative examples show that meeting the smoke density and heatrelease requirements of the EN45545 standard is not possible withregular flame retardant polycarbonate-acrylonitrile-butadiene-styreneblends and flame retardant polycarbonate resins. Formulations andresults are shown in Table 13.

TABLE 13 Unit CEx 40 CEx 41 CEx 42 CEx 43 CEx 44 CEx 45 Component PC1 %0 64.83 51.84 87.55 0 46.78 PC2 % 0 34.59 47.53 0 0 0 PC3 % 87.40 0 0 00 0 PC105B % 0 0 0 12.00 0 1.00 SiPC2 % 0 0 0 0 92.5 46.78 KSS % 0 00.03 0 0 0.25 Rimar % 0 0.08 0 0 0 0.08 Octaphenylcyclotetrasiloxane % 00.10 0 0 0 0 BPADP % 8.00 0 0 0 7.50 5.00 PTFE % 0.20 0 0 0 0 0 ABS R360% 4.00 0 0 0 0 0 Standard additives % 0.40 0.40 0.60 0.35 0 0.12Property Smoke density, DS-4 — 1320 1123 1320 1320 610 814 Heat release,MAHRE kW/m² 140 NA NA NA 153 211

Comparative example 40 is an example of a flame retardantpolycarbonate-acrylonitrile-butadiene-styrene (PC/ABS) blend. Thecomposition has the maximum measurable smoke density value (DS-4) of1320 at 50 kW/m² and a heat release (MAHRE) of 140 kW/m² at 50 kW/m²,which do not meet the EN45545 rail standard (2013) thresholds for R1 orR6 applications for smoke density (DS-4<600 for HL-1, DS-4<300 for HL2and DS-4<150 for HL3, all at 50 kW/m²) and also do not meet the EN45545rail standard (2013) thresholds for heat release (MAHRE<90 kW/m² for HL2and MAHRE<60 kW/m² for HL3, all at 50 kW/m²). Therefore, flame retardantpolycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) blends are notsuitable for seat components or claddings requiring meeting HL2 or HL3requirements of the EN45545 standard.

Comparative examples 41 to 43 are examples of flame retardant bisphenolA polycarbonate resins. All compositions have high smoke density values(Ds-4) above 1000 at 50 kW/m², which do not meet the EN45545 railstandard (2013) thresholds for R1 or R6 applications for smoke density(DS-4<600 for HL-1. DS-4<300 for HL2 and DS-4<150 for HL3, all at 50kW/m²) at any hazard level. Therefore, flame retardant polycarbonateresins are not suitable for seat components or claddings requiringmeeting HL2 or HL3 requirements of the EN45545 standard.

Comparative examples 44 to 45 are examples of flame retardantpoly(carbonate-siloxane) resins. All compositions have high smokedensity values (Ds-4) above 600 at 50 kW/m², which do not meet theEN45545 rail standard (2013) thresholds for R1 or R6 applications forsmoke density (DS-4<600 for HL-1, DS-4<300 for HL2 and DS-4<150 for HL3,all at 50 kW/m²) at any hazard level. Furthermore, these compositionshave heat release (MAHRE) values above 150 kW/m² at 50 kW/m², which donot meet the EN45545 rail standard (2013) thresholds for heat release(MAHRE<90 kW/m² for HL2 and MAHRE<60 kW/m² for HL3, all at 50 kW/m²).Therefore, flame retardant poly(carbonate-siloxane) resins are notsuitable for seat components or claddings requiring meeting HL2 or HL3requirements of the EN45545 standard.

Examples 46-47

These comparative examples show that meeting the smoke density and heatrelease requirements of the EN45545 standard is possible with certainhigh heat polymers, but that these polymers do not have a suitableproperty profile for rail interior applications. Formulations andresults are shown in Table 14.

TABLE 14 Unit CEx 46 CEx 47 Component PEI Wt. % 100 0 PPSU Wt. % 0 100Property Smoke density, DS-4 76 67 Heat release, MAHRE kW/m² 43 15 MVR,300° C., 1.2 kg Cc/10 min Cannot be Cannot be measured measured MV, 300°C., 1500 s⁻¹ Pa · s Cannot be Cannot be measured measured MAI, RT,ductility % 0 0 Glass transition temperature ° C. 216 220

Comparative examples 46 and 47 show that both PEI and PPSU have very lowsmoke density (Ds-4) values around 60-70 and low heat release (MAHRE)values of 43 and 15 kW/m² respectively at 50 kW/m². As such, theseresins are fully compliant with the HL2 or HL3 requirements for R1 andR6 applications according to EN45545 for smoke density (DS-4<300 for HL2and DS-4<150 for HL3, all at 50 kW/m²) and heat release (MAHRE<90 kW/m²for HL2 and MAHRE<60 kW/m² for HL3, all at 50 kW/m²).

However, these resins both have limited practical impact properties, asindicated by their 0% ductility in MAI testing at room temperature.Furthermore, due to their high glass transition temperatures of 216 and220° C. respectively, the melt flow is limited, such that MVR and MVvalues cannot be measured at 300° C., which makes these resins lesssuitable for molding of large and complex parts, using conventionaltooling for PC/ABS and PC resins, which have glass transitiontemperatures of 150° C. and lower, depending on the composition.Furthermore, the high glass transition temperatures of these resins makethem very difficult to form using for instance thermoforming.

As such, despite meeting the HL2 or HL3 requirements for R1 and R6applications according to EN45545 for smoke density (DS-4<300 for HL2and DS-4<150 for HL3, all at 50 kW/m²) and heat release (MAHRE<90 forHL2 and MAHRE<60 for HL3, all at 50 kW/m²), these resins are lesssuitable for molding or forming of rail interior applications.

The singular forms “a.” “an,” and “the” include plural referents unlessthe context clearly dictates otherwise. “Or” means “and/or.” Theendpoints of all ranges directed to the same component or property areinclusive and independently combinable. The suffix “(s)” as used hereinis intended to include both the singular and the plural of the term thatit modifies, thereby including at least one of that term (e.g.,“colorant(s)” includes at least one colorant). “Optional” or“optionally” means that the subsequently described event or circumstancecan or cannot occur, and that the description includes instances wherethe event occurs and instances where it does not. Unless definedotherwise, technical and scientific terms used herein have the samemeaning as is commonly understood by one of skill in the art to whichthis invention belongs.

As used herein, a “combination” is inclusive of blends, mixtures,alloys, reaction products, and the like. Compounds are described usingstandard nomenclature. For example, any position not substituted by anyindicated group is understood to have its valency filled by a bond asindicated, or a hydrogen atom. A dash (“-”) that is not between twoletters or symbols is used to indicate a point of attachment for asubstituent. For example, —CHO is attached through carbon of thecarbonyl group.

As used herein, the term “hydrocarbyl” and “hydrocarbon” refers broadlyto a substituent comprising carbon and hydrogen, optionally with 1 to 3heteroatoms, for example, oxygen, nitrogen, halogen, silicon, sulfur, ora combination comprising at least one of the foregoing; “alkyl” refersto a straight or branched chain, saturated monovalent hydrocarbon group;“alkylene” refers to a straight or branched chain, saturated, divalenthydrocarbon group; “alkylidene” refers to a straight or branched chain,saturated divalent hydrocarbon group, with both valences on a singlecommon carbon atom; “alkenyl” refers to a straight or branched chainmonovalent hydrocarbon group having at least two carbons joined by acarbon-carbon double bond; “cycloalkyl” refers to a non-aromaticmonovalent monocyclic or multicylic hydrocarbon group having at leastthree carbon atoms, “cycloalkenyl” refers to a non-aromatic cyclicdivalent hydrocarbon group having at least three carbon atoms, with atleast one degree of unsaturation; “aryl” refers to an aromaticmonovalent group containing only carbon in the aromatic ring or rings;“arylene” refers to an aromatic divalent group containing only carbon inthe aromatic ring or rings; “alkylaryl” refers to an aryl group that hasbeen substituted with an alkyl group as defined above, with4-methylphenyl being an exemplary alkylaryl group; “arylalkyl” refers toan alkyl group that has been substituted with an aryl group as definedabove, with benzyl being an exemplary arylalkyl group; “acyl” refers toan alkyl group as defined above with the indicated number of carbonatoms attached through a carbonyl carbon bridge (—C(═O)—); “alkoxy”refers to an alkyl group as defined above with the indicated number ofcarbon atoms attached through an oxygen bridge (—O—); and “aryloxy”refers to an aryl group as defined above with the indicated number ofcarbon atoms attached through an oxygen bridge (—O—).

Unless otherwise indicated, each of the foregoing groups can beunsubstituted or substituted, provided that the substitution does notsignificantly adversely affect synthesis, stability, or use of thecompound. The term “substituted” as used herein means that at least onehydrogen on the designated atom or group is replaced with another group,provided that the designated atom's normal valence is not exceeded. Whenthe substituent is oxo (i.e., ═O), then two hydrogens on the atom arereplaced. Combinations of substituents and/or variables are permissibleprovided that the substitutions do not significantly adversely affectsynthesis or use of the compound. Unless otherwise indicated, exemplarygroups that can be present on a “substituted” position include, but arenot limited to, cyano; hydroxyl; nitro; azido; alkanoyl (such as a C₂₋₆alkanoyl group such as acyl); carboxamido; C₁₋₆ or C₁₋₃ alkyl,cycloalkyl, alkenyl, and alkynyl (including groups having at least oneunsaturated linkages and from 2 to 8, or 2 to 6 carbon atoms); C₁₋₆ orC₁₋₃ alkoxy groups; C₆₋₁₀ aryloxy such as phenoxy; C₁₋₆ alkylthio; C₁₋₆or C₁₋₃ alkylsulfinyl; C₁₋₆ or C₁₋₃ alkylsulfonyl; aminodi(C₁₋₆ orC₁₋₃)alkyl; C₆₋₁₂ aryl having at least one aromatic rings (e.g., phenyl,biphenyl, naphthyl, or the like, each ring either substituted orunsubstituted aromatic): C₇₋₁₉ alkylenearyl having 1 to 3 separate orfused rings and from 6 to 18 ring carbon atoms, with benzyl being anexemplary arylalkyl group; or arylalkoxy having 1 to 3 separate or fusedrings and from 6 to 18 ring carbon atoms, with benzyloxy being anexemplary arylalkoxy group.

All references cited herein are incorporated by reference in theirentirety. While typical embodiments have been set forth for the purposeof illustration, the foregoing descriptions should not be deemed to be alimitation on the scope herein. Accordingly, various modifications,adaptations, and alternatives can occur to one skilled in the artwithout departing from the spirit and scope herein.

1-32. (canceled)
 33. A railway component, wherein the component is a molded or extruded train seat component or a molded or extruded interior train cladding, comprising a thermoplastic composition comprising, based on the total weight of the composition: 50 to 93 wt. % of a polycarbonate copolymer comprising bisphenol A carbonate units and units of the formula

wherein R⁵ is hydrogen, phenyl optionally substituted with up to five C₁₋₁₀ alkyl groups, or C₁₋₄ alkyl; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque, an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque, a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque, and a ductility in multiaxial impact of 80 to 100%, measured at 0+23° C. at an impact speed of 4.4 m/second according to ISO 6603 on 3.2 mm thick discs; and when the component is a molded or extruded interior train cladding, the component further has a critical heat flux at extinguishment ((CFE) of equal to or greater than 20 kW/m² measured according to ISO 5658-2 on a 3 mm thick plaque.
 34. (canceled)
 35. (canceled)
 36. The railway component of claim 33, wherein the thermoplastic composition comprises from 4 to 20 wt. % of the poly(carbonate-siloxane) comprising from 1 to 10 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane), and wherein a molded or formed sample of the thermoplastic polymer composition has a transmission of greater than 80% or a haze of 5 or less measured according to ASTM D 1003 using the color space CIE1931 (Illuminant C and a 2° observer) at a thickness of 3 mm.
 37. The railway component of claim 33, wherein R⁵ is phenyl; and E has an average value of 2 to
 60. 38. (canceled)
 39. The railway component of claim 33, wherein the organophosphorus compound is an aromatic organophosphorus compound having at least one organic aromatic group and at least one phosphorus-containing group, or an organic compound having at least one phosphorus-nitrogen bond.
 40. (canceled)
 41. (canceled)
 42. The railway component of claim 33, wherein the thermoplastic composition further comprises 0.05 to 5.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethyleneglycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing.
 43. The railway component of claim 33, wherein the thermoplastic composition further comprises 0.00002 to 5.0 wt. % of a colorant based on the total weight of the polymers in the thermoplastic composition.
 44. The component of claim 33, wherein the thermoplastic composition further comprises 0.1 to 12 wt. % of TiO₂.
 45. The railway component of claim 33, wherein the thermoplastic composition further comprises 5 to 20 wt. % of a bisphenol polycarbonate. 46-58. (canceled)
 59. The railway component of claim 46, wherein the cladding is an interior vertical surface selected from room dividers, flaps, boxes, hoods and louvres; an interior door or lining for internal and external doors; a window insulation; a kitchen interior surface; an interior horizontal surface selected from ceiling paneling, flaps, boxes, hoods and louvres; a luggage storage area selected from overhead and vertical luggage racks, luggage containers and compartments; a driver's desk application selected from paneling and surfaces of driver's desk; an interior surface of gangways selected from interior sides of gangway membranes (bellows) and interior linings; a window frame; an optionally folding table with downward facing surface; an interior or exterior surface of air ducts, a device for passenger information, a side wall, a front wall, an end-wall, a partition, a room divider, an interior door, a window insulation, a lining, a kitchen interior surface, a ceiling panel, an overhead or vertical luggage rack, a luggage container, a luggage compartment, a window frame, an optionally folding table with downward facing surface, an information display screen. 60-62. (canceled)
 63. A railway component, wherein the component is a molded or extruded train seat component or a molded or extruded interior train cladding comprising a thermoplastic composition comprising, based on the total weight of the composition: 50 to 93 wt. % of a combination comprising (i) 5 to 50 wt. % of bisphenol A polycarbonate and (ii) 50 to 95 wt. % of a poly(bisphenol arylate) of the formula

wherein R^(a) and R^(b) are each independently C₁₋₁₂ alkyl, C₁₋₁₂ alkenyl, C₃₋₈ cycloalkyl, or C₁₋₁₂ alkoxy, p and q are each independently 0 to 4, and X^(a) is a bridging group between the two arylene groups, and is a single bond, —O—, —S—, —S(O)—, —S(O)₂—, —C(O)—, a C₁₋₁₁ alkylidene of the formula —C(R^(c))(R^(d))— wherein R and Rd are each independently hydrogen or C₁₋₁₀ alkyl, or a group of the formula —C(═R^(c))— wherein R is a divalent C₁₋₁₀ hydrocarbon group, based on the weight of the combination; 4 to 30 wt. % of a poly(carbonate-siloxane) comprising bisphenol A carbonate units, and siloxane units of the formula

or a combination comprising at least one of the foregoing, wherein E has an average value of 2 to 200, wherein the poly(carbonate-siloxane) comprises 0.5 to 55 wt. % of siloxane units based on the total weight of the poly(carbonate-siloxane); 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing; wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.
 64. The railway component of claim 63, wherein the combination comprises (i) 35 to 45 wt. % of bisphenol A polycarbonate and (ii) 55 to 65 wt. % of a poly(bisphenol A-arylate ester).
 65. (canceled)
 66. (canceled)
 67. A railway component, wherein the component is a molded or extruded train seat component or a molded or extruded interior train cladding comprising a thermoplastic composition comprising, based on the total weight of the composition: 75 to 96.5 wt. % of a poly(bisphenol A carbonate)-co-(bisphenol phthalate ester); 0.5 to 5 wt. % of a poly(siloxane) oil; 3 to 20 wt. % of an organophosphorus compound in an amount effective to provide 0.1 to 2.0 wt. % of phosphorus, based on the total weight of the thermoplastic polymer composition; and and optionally, up to 5 wt. % of an additive selected from a processing aid, a heat stabilizer, an ultra violet light absorber, a colorant, or a combination comprising at least one of the foregoing wherein the component has: a smoke density after 4 minutes (Ds-4) of equal to or less than 300 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², an integral of the smoke density as a function of time up to 4 minutes (VOF4) of equal to or less than 600 measured according to ISO 5659-2 on a 3 mm thick plaque at 50 kW/m², a maximum average heat release (MAHRE) of equal to or less than 90 kW/m² measured according to ISO 5660-1 on a 3 mm thick plaque at 50 kW/m², and a ductility in multiaxial impact of 80 to 100%, measured at +23° C. at an impact speed of 4.4 m/second measured according to ISO 6603 on 3.2 mm thick discs.
 68. (canceled)
 69. The railway component of claim 67, wherein the poly(bisphenol-A carbonate)-co-poly(bisphenol phthalate ester) comprises 75 to 85 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate in the ester units of 98:2 to 88:12.
 70. The railway component of claim 67, wherein the a poly(bisphenol-A carbonate)-co-poly(bisphenol phthalate ester) comprises 35 to 45 wt. % of carbonate units and 55 to 65 wt. % of ester units, wherein the ester units have a molar ratio of isophthalate to terephthalate of 45:55 to 55:45.
 71. The railway component of claim 67, wherein the organophosphorus compound is an aromatic organophosphorus compound having at least one organic aromatic group and at least one phosphorus-containing group, or an organic compound having at least one phosphorus-nitrogen bond.
 72. The railway component of claim 70, wherein the organophosphorus compound of the thermoplastic composition is bisphenol A bis(diphenyl phosphate), triphenyl phosphate, resorcinol bis(diphenyl phosphate), tricresyl phosphate, a phenol/bi-phenol polyphosphate, or a combination comprising at least one of the foregoing.
 73. The railway component of claim 67, wherein the thermoplastic composition further comprises 0.1 to 12 wt. % of TiO₂.
 74. The railway component of claim 67, wherein the thermoplastic composition further comprises 0.05 to 5.0 wt. % of a light diffuser additive comprising silicone, polymethylsilsesquioxane, crosslinked poly(methyl methacrylate), methyl methacrylate/ethylene glycol dimethacrylate copolymer, TiO₂, or a combination comprising at least one of the foregoing.
 75. The railway component of claim 67, wherein the thermoplastic composition further comprises 0.00002 to 5.0 wt. % of a colorant based on the total weight of the polymers in the thermoplastic composition.
 76. The railway component of claim 67, wherein the thermoplastic composition further comprises 5 to 20 wt. % of a bisphenol A polycarbonate. 